Lay tortillas on baking sheet and brush with olive oil. Bake for 6-7 minutes to lightly brown.
Drain and rinse beans; sprinkle onto tortillas.
Spray skillet with cooking spray and heat over medium. Dice onion and bell peppers, mince garlic and chop tomato. Add peppers, onion, garlic and cumin to skillet; cook for 5-6 minutes. Add tomato and cook 1-2 minutes longer. Shred chicken and chop cilantro.
Layer each tortilla with cooked veggies, shredded chicken and cilantro.
Return to oven and bake for 2 minutes. Top tostadas with avocado slices and cheddar cheese. Serve with cubed mango.