Instead of serving this on tortillas, put it on a bed of spinach with avocado and fresh tomatoes!

2 pounds flank or skirt steak 2 tablespoons white vinegar 4 cloves garlic, minced 2 limes, juiced 1/2 cup olive oil 1 jalapeno, seeded and minced 1/2 teaspoon salt 1/2 teaspoon ground black pepper 1/2 teaspoon sugar 1 teaspoon ground cumin 1 large handful of cilantro, stems and leaves chopped 1/2 teaspoon chili powder and 1/2 teaspoon cayenne pepper (only if you like it spicy)

1. Lay the flank steak in a bowl or baking dish. Combine marinade ingredients and pour the marinade over the steak. Make sure each piece is well coated. Cover in plastic wrap and refrigerate forever. Or as long as possible- I do it 2 or 3 days for Glamis, but 24 hours is what I do at home.
2. Preheat your grill over medium-high flame (you can also use a cast iron grill pan on high heat for stove-top cooking). Brush the grates with a little oil to prevent the meat from sticking. Remove the steak from the marinade. If you are cooking indoors, you may want to brush off excess marinade as the bits may burn and smoke on the hot pan. Season both sides of the steak pieces with salt and pepper. Grill the pieces for a few minutes only, on each side, depending on how thin they are, until medium rare to well done, to your preference. You may need to work in batches.
3. Remove the steak pieces to a cutting board and let rest for 5 minutes. Thinly slice the steak across the grain on a diagonal.