4.8 from 23 reviews

Trust me, you’re going to want to hold onto this recipe for healthy Stuffed Shells with Spinach, because when you try it, and you proceed to watch your family devour the entire pan, you’ll want to make it over and over again.

The shells are made with vegetarian filling with onions, spinach, ricotta and a secret healthy ingredient nobody will even know is there! It is such an easy win! Plus it can be prepped ahead so it works for entertaining or you can meal prep it (or freeze it) and have it on a weeknight too! 

healthy stuffed shells with spinach topped with cheese in a casserole dish

Table of contents

Why We Love These Healthy Stuffed Shells with Spinach

I cannot believe that I have never made stuffed shells in my entire life until these Healthy Stuffed Shells came along. I think I had always assumed that a) they were too labor intensive and b) too unhealthy.

Well, let me tell you dear reader, these Stuffed Shells with Spinach are neither! I cannot wait to share them with you so you can join me in making stuffed shells on repeat from now on! 

I decided I wanted to try making them for you this month because I thought they would make a good make-ahead recipe. So when I started out on the task of developing the recipe I actually built the make-ahead right into the recipe.

And the good news is that it just lends itself to prepping ahead! Not only can you prep it the day before, but you can actually freeze it too!

So if you have guests coming, or you find yourself on a Sunday with some extra time on your hands, make a batch of these shells and you can thank me later.

Let’s get into the deets about the shells because I am bursting at the seams to tell you about the SECRET INGREDIENT!!!

a single stuffed shell with spinach lifted out of the dish with cheese hanging from the spoon

Key Ingredients for This Recipe

Pasta Shells

Since I was new to shells, I was not aware of the fact that there is such a thing as Jumbo Shells. And that is exactly what you need for this recipe. 

I tested this with Prince and Barilla, and they both worked well. I found the Prince ones were slightly easier to fill because the Barilla ones curled up on themselves a bit too much, so it was hard to get the spoon of filling into the shell without making a mess.

Either way, you don’t need a whole box. I am not sure why they sell them in such large boxes, because you can’t possibly fit an entire box, filled, into a 9 by 13 casserole dish. I found that 9 ounces was plenty with a couple of extras for those that break or tear in the boiling process.  

Ricotta and Additional Fillings

When you think about it, ricotta doesn’t have much flavor on its own, so the key to making a delicious stuffed shell is to amp up the flavor as much as possible. Note, I use part-skim ricotta. This is much lower in fat than whole-milk ricotta, but because we add in so much flavor, you won’t miss the extra fat, and it will save tons of calories! I use a whole 15 (or 16) ounce container of ricotta. 

Tofu

Here’s where the secret ingredient comes in! That’s right, there’s tofu in these shells! You would never know by tasting them because it crumbles right into the ricotta filling and you can’t taste it at all, and the texture really blends in entirely. Nobody in my family even noticed at all. Even my 11-year-old who has some “texture issues” loved it! 

By using the tofu instead of an additional cup of ricotta, you’ll save about 9 grams of saturated fat and it’s still high in protein and calcium. 

If you read this far but still need a little convincing, listen… I googled “stealthy tofu ricotta”, and they even make lasagna with it over on the Kitchn, so apparently I am not the only person with the idea! If you swear you hate tofu, give this a try. 

If you’re new to tofu here’s what you need to know.

  1. Buy Extra Firm Tofu. Not baked (which is too hard and dry) and not silken (which is very soft and pudding-like.)
  2. Look for tofu packed in water, often sold in the produce department. 
  3. I like to buy the mini packets of organic Nasoya Extra-firm tofu, if you can find them. They’re just the right size for this recipe. If not, you can buy the full-size block, and cut it in half. Make sure to store the leftover tofu in water.
  4. Because the tofu is packed in water, you’ll need to take a moment to dry it off. I like to pat it dry before crumbling it, and then after. I use dry paper towels to do so. 
  5. Once the tofu is patted dry, you can literally crush the tofu in your hands, and it will break apart into crumbles that mimic ricotta cheese. (See video!) I crumble it right onto a plate lined with more paper towels. 

Part Skim Mozzarella Cheese

I buy the pre-shredded part-skim mozzarella because it’s so easy. I know it’s not the greatest melting cheese on the planet, but it helps keep the calories and fat in check. I use 6 ounces for the whole casserole. 

Step By Step Instructions For Spinach Stuffed Shells

Step 1: Boil Shells

Bring a large pot of salted water to a boil over high heat and add shells to cook for 2 minutes less than the package instructions. Cooking them 2 minutes less will yield shells that are soft enough to work with and fill, but not so soft that they become mushy once filled and baked. Drain shells well and rinse with cold water.

sauteed spinach

Step 2: Sauteé Spinach, Onion & Garlic

Meanwhile, heat oil in a large non-stick skillet over medium-high heat and add garlic and onion to cook, stirring often until softened and browned, which should take 3 to 5 minutes.

Add in dry Italian seasoning. I always keep Italian Seasoning on hand because it’s like using three or four herbs in one. I also use it in my beef lasagna, chicken cacciatore, and minestrone too. Stir it into the hot vegetables right when you remove it from the heat so the heat will help to activate the seasoning a bit.

Set the skillet aside to let the veggies cool a bit. You’ll be mixing them with the rest of the filling mixture, including the eggs, so you want the veggies to be cool.

Crumble tofu

Step 3: Crumble Tofu and Pat Dry

Drain the tofu and pat dry with paper towels. Crush the tofu into crumbles over more paper towels into small chunks and pat dry again. Then, transfer the mixture to a large bowl.

Adding the spinach to the ricotta mixture for shell stuffing

Step 4: Combine Spinach Mixture with Ricotta

Add ricotta, egg, Parmesan, salt, and pepper to the tofu and stir to combine. Add the spinach mixture and stir again.

sauce in the bottom of the casserole dish

Step 5: Prep Dish and Spread Tomato Sauce

Preheat the oven to 350 degrees F. Coat a 9 by 13-inch casserole dish with cooking spray and spread ½ cup tomato sauce over the bottom of the casserole dish.

Top the shells with the remaining 1 1/2 cup sauce and basil.

Step 6: Fill Shells and Assemble

Taking one shell at a time into your hand, spoon spinach filling into the shell (about 2 tablespoons per shell.) Set the shell into the casserole. Continue stuffing shells using all of the filling, and arrange them filling side up. Pour the remaining 1 ½ cups of sauce over the shells and top with basil and then mozzarella.

Top the shells with cheese

Step 7: Bake and Serve

Bake until the sauce is bubbling, the shells are hot all the way through, and the cheese is melted, which should take about 25 minutes. Remove the dish from the oven, and let it cool for about 5 minutes. Sprinkle with additional basil and Parmesan if desired, and serve.

Vegetarian Stuffed Shells with Tofu and Spinach in a casserole dish

FAQs and Expert Tips

How do I cook stuffed shells from frozen?

I am pleased to report that these stuffed shells can be frozen and then baked (directly from the freezer) and the results are AMAZING!

To do so, first, make sure you have a casserole dish that allows you to go from the freezer to the oven. Then prepare the shells through step 6. Wrap the entire casserole dish twice with plastic wrap. Then wrap on top with foil. Freeze for up to one month. To reheat this dish, remove the plastic wrap and then cover the casserole dish with foil. Transfer directly to the oven and bake for 1 hour and 10 minutes. Remove the foil and bake for an additional 10 minutes. 

What goes with stuffed shells?

I like to make a salad with Lemon Vinaigrette to serve with them. You could also make these Green Beans with Walnuts and Balsamic. If you’re serving this to guests, for dessert, serve either my Apple Cake or the Gingerbread Cake with Cream Cheese Frosting. 

Tips For Making This Recipe in Advance

If you are meal prepping this Stuffed Shells recipe, after you fill the shells, and assemble the casserole, you can refrigerate them for a day before baking them. Just cover the casserole dish with aluminum foil and pop it into the fridge. 

Then preheat your oven to 350 degrees, and set the casserole into the oven with the foil on it. The foil will help trap in the steam as it comes up to temp. Then you can remove the foil and bake it for 15 or so minutes longer, just look for the sauce to bubble and the cheese to melt. 

Tips for Assembling Your Shells

  • Start out with clean hands. This is kind of a messy process, so you’ll want to try to start as clean as you can. 
  • Coat the casserole dish with cooking spray and then spread some of the tomato basil sauce in the bottom of the casserole dish. The sauce will prevent the shells from sticking. 
  • Working one at a time, pick up a shell with your non-dominant hand, and a spoon with the other. Scoop filling (about 2 tablespoons) into the shell. Set the shell down into the prepared pan, filling side up. Repeat with all the shells and filling, arranging them into rows in the casserole dish. 
  • Pour the rest of the tomato basil sauce over the top of the shells.
  • Next, add more flavor in the form of freshly chopped basil. This is such a yummy addition, and it really takes the flavors to the next level! Don’t skip it! I put it under the cheese so that the basil doesn’t turn black and burn when it bakes. 

Additional Recipes To Try

Thanks so much for reading! If you are new here, you may want to sign up for my email newsletter to get a free weekly menu plan and the latest recipes right to your inbox. If you make this recipe, please come back and leave a star rating and review. I would love to hear what you thought!

Happy Cooking! ~Katie

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close up photo of healthy stuffed shells with spinach

Healthy Stuffed Shells with Spinach

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4.8 from 23 reviews

  • Author: Katie
  • Total Time: 55 minutes
  • Yield: 6 servings 1x
Print Recipe

Description

These Stuffed Shells with Spinach are a healthy vegetarian make-ahead casserole for meal-prep or to serve to company.

Ingredients

Scale

9 ounces jumbo shells pasta

1 tablespoon extra-virgin olive oil

3 cloves garlic, minced

1 cup chopped red onion

1 5-ounce box baby spinach

2 teaspoons Italian Seasoning

7 ounces extra-firm tofu (not silken)

1 15-ounce container part-skim ricotta cheese

1/3 cup grated Parmesan cheese plus more for serving

1 large egg

1 1/2 teaspoon salt

Freshly ground pepper to taste

2 cups tomato basil sauce, divided

2 tablespoons chopped fresh basil, plus more for serving

1 1/2 cup shredded part skim mozzarella cheese (6 oz)

Instructions

  1. Bring a large pot of salted water to a boil over high heat. Add shells and cook for 2 minutes less than package instructions. Drain well and rinse with cold water.
  2. Meanwhile, heat oil in a large non-stick skillet over medium-high heat. Add garlic and onion and cook, stirring often until softened and browned, 3 to 5 minutes. Stir in spinach and Italian seasoning until the spinach is wilted and remove from the heat.
  3. Drain tofu and pat dry with paper towels. Crush tofu into crumbles over more paper towels into small chunks and pat dry again. Transfer to a large bowl.
  4. Add ricotta, egg, Parmesan, salt and pepper to the tofu and stir to combine. Add the spinach mixture and stir again.
  5. Preheat oven to 350 degrees F. Coat a 9 by 13 inch casserole dish with cooking spray. Spread ½ cup tomato sauce over the bottom of the casserole dish.
  6. Taking one shell at a time into hand, spoon spinach filling into the shell (about 2 tablespoons per shell.) Set the shell into the casserole. Continue stuffing shells using all of the filling, and arranging them, filling side up. Pour the remaining 1 ½ cups sauce over the shells. Top with basil and then mozzarella.
  7. Bake until the sauce is bubbling, the shells are hot all the way through and the cheese is melted, about 25 minutes. Remove from the oven, and let cool about 5 minutes. Sprinkle with additional basil and Parmesan if desired, and serve.

Notes

Make Ahead: Do not preheat oven in step 5. Assemble the shells as directed. Cover and refrigerate up to 24 hours in advance. Preheat oven to 350 degrees. Bake covered until hot all the way through, about 35 minutes. Then remove foil and continue baking as directed until the shells are steaming hot, the sauce is bubbling and the cheese is melted, about 15 minutes longer.

To Freeze Ahead: To do so, first make sure you have a casserole dish that allows you to go from freezer to oven. Then prepare the shells through step 6. Wrap the entire casserole dish twice with plastic wrap. Then wrap on top with foil. Freeze for up to one month. To reheat: remove the plastic wrap and then cover the casserole dish with foil. Transfer directly to the oven and bake for 1 hour 10 minutes. Remove the foil and bake for an additional 10 minutes.

  • Prep Time: 30
  • Cook Time: 25
  • Category: Main Course
  • Method: Oven
  • Cuisine: Italian

Nutrition

  • Serving Size: 1/6 casserole (about 3 to 4 shells)
  • Calories: 446
  • Fat: 18 grams
  • Saturated Fat: 8 grams
  • Carbohydrates: 49 grams
  • Fiber: 7 grams
  • Protein: 28 grams

Did you make this recipe?

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This Recipe is Part of A Meal Prep Menu

This stuffed shells recipe is part of my Meal Prep Menu which also includes four more make-ahead dinners. In this plan, I give you the prep list, shopping list, and plan to prep on the weekend, so you can have all your weeknight meals ready to go with 20 minutes (or less) of time in the kitchen! 

Here’s the complete menu:

  1. Monday: Stuffed Shells with Spinach and salad with Lemon Dressing
  2. Tuesday: Cod Fish Tacos with refried black beans
  3. Wednesday: Sloppy Joes and Roasted Broccoli and Cauliflower with Cheese
  4. Thursday: Chicken and Wild Rice Soup
  5. Friday: Greek Pizza and lemony green beans

You may also love these Vegetarian Stuffed Peppers with Italian Flavors. Feel free to swap them in for any of the meals on this menu. To get the full details, print your shopping list, and get started, head over to the Meal Prep Menu to check it out!