In a large bowl, combine 1 cup salsa, 1 tbsp diced ginger (if using), 1 diced jalapeño (pith and seeds removed), 1/4 cup olive oil (optional), and 1 tbsp BBQ rub or taco seasoning; mix until evenly combined.
Add the 3 lb steak to the bowl and coat it thoroughly with the salsa mixture, using tongs to turn and spread the marinade over all surfaces.
Cover the bowl with plastic wrap or a lid and refrigerate; marinate for at least 20–30 minutes, or up to 3–4 hours for more flavor.
Before grilling or smoking, remove the steak from the marinade and pat it dry with paper towels to help achieve a better sear.
Grill or smoke the steak to your desired doneness, then rest briefly before slicing and serving.