Preheat broiler to the high setting in your oven. Slice peppers, onion, and mushrooms into large strips.  Arrange on a broiler pan, drizzle with olive oil and sprinkle with salt.

Cook the vegetables in the oven for about 10-15 minutes, or until the vegetables are tender and start to get browned on top.

While vegetables are in the oven, Mix chili powder in with the beef, mold into 4-6 patties; depending on sizes desired.

Heat a skillet to medium high, and cook the burger patties on each side, until no longer pink in the middle..

Serve patty inside a hamburger, topped with the vegetables, salsa and plain yogurt. Slice mangoes and serve with mango slices.