Preheat oven to 400°F. Line a baking sheet with foil.
Season chicken pieces all over with chili powder, onion powder, garlic powder, cumin and salt and pepper.
Heat olive oil in a large skillet over medium heat. Add chicken pieces and cook, turning once, until golden brown and cooked through.
Remove to a plate, allow to rest for a few minutes and then shred into small pieces.
Place chicken in a large bowl. Add ranch, ½ cup of shredded cheese, and cilantro.
Place a big spoonful of filling down the center of each tortilla.
Bring the bottom edge of the tortilla tightly over the filling, folding in the sides and rolling it up into a burrito.
Place burritos on lined baking sheet and brush them with olive oil or spray with non stick cooking spray.
Bake at 400°F for about 20-25 minutes or until golden brown and crispy.
Meanwhile, prepare sauce by melting butter and olive oil in a medium saucepan over medium heat.
Whisk in flour and cook, stirring constantly for about 2 minutes.
Add cumin. Gradually whisk in chicken broth and cook, stirring, until slightly thickened, about 3 minutes. Remove from heat and stir in ranch seasoning and sour cream.
Remove burritos from oven and turn the oven to HIGH broil.
Ladle a spoonful of sauce over each burrito and top with a handful of shredded cheese.
Broil for 2-3 minutes, or is melted and bubbly. Remove from oven and top with diced avocados and tomatoes. Enjoy!
