I can guarantee you will not be disappointed when you try this tomato-marinated grilled flank steak. It’s so simple and the delicious tomato, vinegar, and herb marinade doubles as the mop sauce, which transforms the grass-fed steak into a tender and juicy dinner to remember!

marinated grilled flank steak and cucumbers on a black plate

Why We Love This Recipe For Marinated Grilled Flank Steak

As a vegetable gardener, when tomatoes are in season, I try to add them to as many recipes as possible. I’ve even been known to add them to my salad dressings! Seriously, try my Smoky Tomato Salad Dressing. Today I am sharing a way of adding them to marinade for grilled flank steak.

The seasoning and tomato marinade are the keys to this recipe, so one of the things I love most about this flank steak is that some of the marinade is set aside before you add the meat to be used as a mop sauce. Basting the marinade over the meat as it’s grilling gives you an even juicier flavor!

I paired this delicious marinated grilled flank steak with my simple skinny cucumber salad for a light side dish, but it would also be great with Ratatouille! Leftovers would be great for Steak Salad, and wow, now I want steak salad, but since steak and potatoes are kind of a thing, check out a few of my yummy potato side dishes.

a close up of tomato and herb marinated flank steak

Key Ingredients for This Marinated Grilled Flank Steak Recipe

Flank Steak (Grass-Fed)

If your budget allows, try to use grass-fed beef for this recipe. It is stronger in flavor, but the herbs, shallot and acidity of the marinade really cuts the gaminess of the meat.

Tomato

I used a beefsteak tomato for this recipe, cored and chopped. You can use any other slicing tomato though.

Herbs

You’ll want to focus on rosemary and marjoram. Marjoram is very similar to oregano, so if you can’t find any you can swap it for oregano – but marjoram does have a slightly sweeter flavor to it.

Additional Ingredients

  • Shallot
  • Red wine vinegar
  • Salt and pepper
a platter of flank steak and a plate with cucumbers and steak

Step-By-Step Instructions

Step 1: Marinade

Puree the tomato, shallot, vinegar, marjoram, rosemary, salt, and pepper in a blender until it’s smooth. Reserve 1/2 a cup for the mop. Scrape the remaining tomato mixture into a re-sealable plastic bag and add the steak. Turn it to coat, and then refrigerate for at least 4 hours, or overnight.

Step 2: Grill Flank Steak

Prepare your grill for medium-high heat. Remove the steak from the marinade and discard the leftovers in the bag. Oil your grill rack.

Grill your steak for about 5 minutes per side for medium-rare, 6-7 minutes for medium, and 8 minutes for medium-well. After turning the meat, brush the first cooked side with the reserved mop sauce.

Brush mop sauce over the second cooked side and remove the meat to a platter to rest for 5 minutes. Slice against the grain, and serve your flank steak with any remaining mop spooned over the sliced meat.

sliced flank steak beside tomatoes, herbs, and cucumbers

FAQs and Tips

What’s the benefit of marinating grass-fed beef?

If you are blessed with enough time, marinating a cut like flank steak for a full 24 hours is worth the wait. Grass-fed beef can be a little gamey, akin to lamb or even venison, but if you marinate it in a boldly-flavored marinade you balance those flavors. Something with a good deal of acid like vinegar or citrus really works its way into the meat.

How do I not overcook grassfed beef?

Grass-fed beef is lean, so err on the side of cooking it a little less than you normally would. And I recommend turning it more often, too. After the first couple of times, you’ll get the hang of it and be a grass-fed beef cooking pro!

Serving Suggestions

More Steak Recipes

Thanks so much for reading. If you are new here, you may want to sign up for my free weekly email newsletter where I share weeknight meal plans delivered right to your inbox. Or follow me on Instagram. If you make this recipe, please come back and leave a star rating and review! It is very appreciated. Happy Cooking! ~Katie

Print
clock clock iconcutlery cutlery iconflag flag iconfolder folder iconinstagram instagram iconpinterest pinterest iconfacebook facebook iconprint print iconsquares squares iconheart heart iconheart solid heart solid icon
Grilled Flank Steak with Tomato Herb Mop Sauce is a simple paleo-friendly dinner featuring grass-fed flank steak. | Healthy Seasonal Recipes | Katie Webster #paleo #grilling #grassfedbeef

Tomato Marinated Grilled Flank Steak


  • Author: Katie Webster
  • Total Time: 24 hours
  • Yield: 6 servings 1x

Description

I can guarantee you will not be disappointed when you try this marinated grilled flank steak with grilled tomatoes and herbs. It’s so simple and the delicious tomato, vinegar, and herb marinade doubles as the mop sauce, which transforms the grass-fed steak into a tender and juicy dinner to remember!


Ingredients

Scale
  • 1 medium slicing tomato, such as beefsteak, cored and chopped
  • 1 shallot peeled and quartered
  • ¼ cup red wine vinegar
  • 2 tablespoons chopped marjoram
  • 1 tablespoon chopped rosemary
  • 1 teaspoon salt
  • ½ teaspoon freshly ground pepper
  • 1 ½ pounds flank steak, preferably grass-fed, fat trimmed

Instructions

  1. Puree tomato, shallot, vinegar, marjoram, rosemary, salt and pepper in blender until smooth. Reserve ½ cup for mop. Scrape the remaining tomato mixture into a re-sealable plastic bag. Add steak and turn to coat. Refrigerate 4 hours or overnight.
  2. Prepare grill to medium high heat. Remove steak from marinade and discard any left-over marinade. Oil grill rack. (see how to do that in this post.) Grill steak about 5 minutes per side for medium-rare, 6 to 7 minutes per side for medium and 8 minutes per side for medium-well; after turning meat brush first cooked side with mop.   Brush mop over second cooked side and remove to a platter to rest 5 minutes. Slice against the grain and serve with any remaining mop spooned over sliced meat.

Notes

Marjoram can be substituted with oregano if necessary, but keep in mind that the marinade will lose some of its sweetness. 

  • Prep Time: 45 minutes
  • Cook Time: 12 minutes
  • Category: Main Course
  • Method: Grilling
  • Cuisine: American

Nutrition

  • Serving Size: 3 1/2 ounces each
  • Calories: 164
  • Sugar: 0 g
  • Sodium: 289 mg
  • Fat: 6 g
  • Carbohydrates: 1 g
  • Fiber: 0 g
  • Protein: 25 g
  • Cholesterol: 85 mg

Keywords: grilled tomato herb flank steak, marinated grilled flank steak,Tomato Marinade

This recipe was originally developed for EatingWell Magazine and it appeared in the July August 2009 issue. I then shared this recipe here on July 15, 2011. I have updated the blog images and some of the text today.