Flank Steak Marinade: 1/2 cup Vegetable Oil 1 Tablespoon Yellow Mustard 1/4 cup Red wine vinegar Crushed Black Peppercorn 1 Tablespoon Minced Garlic Juice Of 1 lemon 1/3 Cup Soy Sauce Place flank steak in a large ziplock bag and add all marinade ingredients. Marinate in the fridge for about 2 hours. Prepare grill the grill! Stack coals, light, and let coals become a bit ashy for 15 minutes. Add grill grate and brush on oil. Let grill grate preheat 15 minutes. While the grill is getting hot, get all your favorite fajita toppings ready. I cooked peppers and onions on the stove, microwaved some flour tortillas, diced tomato, avocado, lettuce, shredded cheese, and put out the sour cream, salsa, and hot sauce. When the grill is at medium-high heat grill the flank steak about *10 minutes per side. This time will change based on the thickness of your flank steak and your doneness preference! Our flank steak was very thick, about 2 inches th...