Heat olive oil in a saucepan over medium heat; cook onion until tender (approx. 5-10 minutes).
Stir in black beans, salsa, garlic powder, chili powder with onion.
Reduce heat to low and cook mixture at a simmer until thickens (approx. 5-10 minutes).
Serve with taco shells (soft or hard), tomato, avocado and shredded lettuce.