Tenderize meat with a tenderizing mallet. Squeeze lime juice onto meat with a squeezer/juicer and sprinkle with seasoning salt (I use Johnny's) and black pepper.
Finely chop onion and cilantro and put to the side.
Barbecue meat until just a slight amount of pink remains in the middle. Cut meat into small cubes and place in foil. Keep meat warm in the oven or away from the flame in the barbecue.
Heat refried beans in a small sauce pan. (Rosarita tastes the closest to homemade to me).
Place a small amount of canola oil into the bottom of a frying pan or iron skillet. Over medium heat, warm the tortillas, turning over once.
Spread a small amount of refried beans onto the center of the tortillas. Add meat, shredded cabbage, cilantro/onion mixture, jalapeno slice and a slice of avocado (if desired). Top with salsa verde and serve with key limes.