Cook peppers and onions in 2 tablespoons butter until tender-crisp. Stir in cumin. Remove vegetables from pan. Melt remaining 1 tablespoon butter in skillet. Set aside.

Sprinkle 1/4 cup cheese on each tortilla; top each with pepper mixture. Fold tortillas in half, place on cookie sheet. Brush lightly with reserved melted butter.

Bake 5 to 7 minutes or until cheese is melted. Cut each tortilla in thirds to form triangles. Serve warm with salsa.