A good marinade for carne asada requires garlic, cilantro, a lager-style beer, limes, olive oil, chili powder, ground cumin, oregano, ground chipotle chili and salt. It's best to use a food processor or blender to make the marinade so all the ingredients are completely incorporated.
Turn on the food processor and use it to finely chop 2 cloves of garlic. Add 1/3 cup of fresh cilantro leaves to the food processor's storage container and pulse the machine a few times to coarsely chop the cilantro together with the garlic. Turn the processor on once again and add 1/2 cup of lager-style beer, the zest of a lime, and 1/4 cup each of lime juice and olive oil. Also add 1 tablespoon of chili powder, 1 teaspoon each of ground cumin and oregano, 1/4 teaspoon of ground chipotle chili and 1/2 teaspoon of salt while the processor runs.
Place the carne asada steak into a glass baking dish and pour the marinade over the top of it. Cover the top of the baking dish with plastic wrap to seal the meat inside. Refrigerate the meat and the marinade together for anywhere between four and 24 hours. Turn the meat occasionally to marinate all portions properly.