In a medium bowl, whisk together all of the ingredients except for the steak.
Place the steak in a large baking dish or gallon size ziplock bag and pour the marinade on top. Turn the steak a few times until it's completely coated with the marinade and refrigerate for 2 to 4 hours. Do not marinate for longer than 8 hours because the meat will start to break down and get mushy due to the acidity in the marinade.
Remove steak from marinade and discard any excess marinade. Pat steak dry with paper towels and drizzle with a touch of olive oil, enough to coat each side. Season lightly with coarse salt and black pepper on both sides.
Preheat grill (or grill pan) to medium-high heat (400-450°F). Grill steaks with the lid closed for 4-8 minutes per side, depending on the thickness. Skirt steak will be closer to 4 minutes per side and flank steak will be closer to 6-8 minutes per side.
Remove steaks and allow to rest for 5 minutes. Slice into bite-sized chunks for easy eating in tacos.
For the tacos
Place a heaping spoonful or two of carne asada onto warm tortillas.
Top with diced onions, chopped cilantro, crumbled cotija cheese and a spritz of fresh lime juice.
Serve with more of your favorite toppings like guacamole, pico de gallo and salsa if desired.
To keep your tortillas warm and pliable when serving, place them inside a tortilla warmer like this or wrap them in a clean kitchen towel and place them inside a large gallon-sized zip top bag to help them retain heat and moisture.