Preheat oven to 400 degrees F.

If chicken breast is more than 1-inch thick, lay it on cutting board and cover with sheet of parchment paper. Use small pan to flatten/pound chicken to 1-inch thickness. (Note: This will ensure quick and even cooking.) Arrange chicken in baking dish or cast iron skillet.

In mixing bowl, whisk together all marinade ingredients and brush on all sides of chicken until fully coated. Cover dish and marinate 10 minutes.

On sheet pan, place sliced onion and peppers, sprinkle with 1 tablespoon oil and ¼ teaspoon salt and toss to coat.

In oven, place sheet pan with peppers and onion and uncovered dish with chicken; bake 25 minutes or until veggies are tender and chicken reaches internal temperature of 165 degrees F.

Prep tortillas by placing each in turns in warm, dry pan, about 30-60 seconds per side.

Slice or shred chicken into rough strips in baking dish and add peppers and onions. Toss to combine. Serve with tortillas and garnishes of choice.