Heat olive oil in a frying pan over medium heat. Add the onion, garlic and capsicum to the pan and stir fry for 1-2 minutes, or until just softened.
Add chilli powder, paprika, diced tomatoes, kidney beans, black beans and zucchini. Bring to the boil, then reduce heat to low and simmer for 5-10 minutes or until slightly reduced.
Fill tortillas with bean mixture, grated cheese and a dollop of sour cream.