These were awesome! I Googled around looking for grilling tips for the flat iron steaks we love so well and found plenty of recipes for marinades. I combined a few of the more interesting ones and came up with a marinade that worked fine for me today. Naturally, I didn’t write anything down because that’s no fun, but here goes off the top of my head: Olive oil, balsamic vinegar, chili powder (I used ancho powder), ground cumin, minced garlic, black pepper, and salt.
Let the meat marinate for at least an hour, then toss it onto a hot grill – this one got about 6 minutes a side, turn the heat from medium high to medium on the turn. Let the steak rest while you stir fry the onions and peppers. I sprinkled a little fajita seasoning over them for a touch of flavor.
Slice the steak across the grain, and serve over a lightly fried tortilla with the cooked veggies. I made a topping from sour cream and chipotle chili powder with three or four cloves of crushed and minced garlic.