In a medium mixing bowl, whisk together the soy sauce, vinegar, olive oil, salt, minced garlic, rosemary, Italian seasoning, Dijon mustard, brown sugar, and black pepper together until combined and the brown sugar is dissolved.
Add the steak to the marinade. Turn to cover. Cover the bowl with plastic wrap or a lid and marinate the steak refrigerated for 6-12 hours, turning once or twice if possible.
Preheat the grill to medium-high heat (or 375 to 400 degrees Fahrenheit).
Add the steak to the grill, pouring the remaining marinade over the steak or discarding the marinade. Grill the steak for 7-11 minutes, turning every 2 or 3 minutes, or until the steak has reached your desired degree of doneness (see a doneness guide jn the recipe notes below).
Notes
1. Leftovers last refrigerated in a covered container for 4-5 days. They do not freeze well. 2. To make this recipe gluten-free, substitute coconut liquid aminos or tamari sauce for the soy sauce. To make this recipe processed sugar-free, substitute raw honey or maple syrup for the brown sugar.3. For a steak degree of doneness guide, click here.4. This marinade is great on other cuts of steak, too, like flank steak, tri-tip, and sirloin, and more. 5. If you are salt sensitive or are on a low sodium diet, decrease the salt in this recipe to ¼ teaspoon or omit it entirely.
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