Heat a skillet over medium. Mix cumin, chili powder, and salt in a small bowl.
Thinly slice onion, pepper and zucchini. Toss together in a bowl with 1/2 the seasoning.
Cut chicken into small strips and toss with remaining seasoning.
Add chicken to skillet and cook until no longer pink; approximately 5-6 minutes. Add in the veggies and cook for an additional 2-3 minutes; stirring occasionally.
Meanwhile, grate the cheddar cheese.
Heat another large skillet over medium. Once hot, add one tortilla and place 1/4 of veggie and chicken mixture on 1/2 the tortilla. Sprinkle on the cheese and fold over. Allow to cook for 1 minute and flip; allowing each side to slightly brown and the cheese to melt. Remove from skillet in cut into triangles.
Continue until all servings have been cooked.
Serve with salsa for topping and sliced nectarines on the side.