Place pineapple juice, soy sauce, lime juice, cilantro, jalapeño, onion, water, black pepper, and cumin in a bowl or large zip lock bag. Add steak to the bag. Allow it to marinate for about 4 hours (you can shorten this time if in a rush).
Place oil in cast iron skillet. Allow skillet to get hot before placing steak on it. Make sure there isn’t too much moisture on the steak. Too much moisture on the steak can decrease the browning of the steak.
Cook until preferred temperature. Remove steak from heat.
Add 1 tbsp of oil if needed to empty pan. Add onions and bell peppers to the pan and cook until vegetables begin to soften, about 4-5 minutes.Add salt and pepper to taste.
Cut steak against the grain. Serve hot with your choice of tortilla.