Season the steak with the salt and pepper. In a bowl, whisk together the olive oil, brown sugar, soy sauce, worcestershire sauce, garlic and ginger. Place the steak in a ziplock bag or a baking dish and pour the marinade over top. Place the steak in the fridge and marinate for anywhere from 2 to 24 hours, flipping the steak occasionally.
When you’re ready to cook the steak, you can either grill it over high heat for about 5 minutes per side, cook it in a skillet over high heat for about 4 to 5 minutes per side, or place it under the broiler (on high) for 4 to 5 minutes per side. Let the steak sit for 10 to 15 minutes before slicing, then cut against the grain and slice thin strips.
To assemble the tacos, serve with warmed tortillas, queso fresco and the pineapple pico.