Slice pepper and onion. In crockpot, place the chicken, sliced pepper, sliced onion, mushrooms, vegetable broth and taco seasoning. Cook covered, on high for 4 hours.
Just before serving, peel and grate carrots and cut melon into cubes.
Remove chicken and vegetables from crockpot; shred chicken.
Place warm chicken inside tortilla wraps topped w/ carrots, cheese & yogurt, if desired. Serve melon cubes on the side.