There are a couple of options you can use for the beef. Flank steak or skirt steak are great options. They are already fairly thin cuts that absorb marinade well and take minimal time to cook. Top sirloin, ribeye, NY strip, flat iron, and hangar steaks are all acceptable substitutes. I am using a flank steak.
Mix the soy sauce, lime juice, minced garlic, onion, and black pepper together.
Pour the marinade over the meat. Let the flank marinate for a couple of hours. Overnight is even better.
There are a couple different ways you can cook this. A charcoal grill works the best and gives it the best flavor. You can cook this on a grill pan on the stove top. I decided to use my broiler. Regardless of how you cook the meat, let it rest at room temperature for 30 minutes before cooking.
Preheat your broiler for a good 10 minutes. Set your oven rack 6 inches away. Put the flank on a rack on a foil covered baking sheet. Broil the flank steak for 8 minutes a side. Let rest for 10-15 minutes.
Once the flank is done resting, slice it thin against the grain.
Carne Asada can be served with some beans and rice with some avocado. Or you can turn it into tacos like I did with; topped off with homemade Serrano pepper hot sauce, real Mexican sour cream, and cilantro/onion/green onion mix.