Carol-I've only ever served this warm but the cold leftovers are good so I think it would work for a do-ahead.
{ Exported from MasterCook Mac }

Turkey Breast With Tequila Sunrise Sauce

Recipe By: Light and Spicy
Serving Size: 10
Preparation Time: 0:00
Categories: Poultry

Amount Measure Ingredient Preparation Method
1 turkey breast about 3 pounds
2 large onions sliced
1 1/2 cups orange juice
1/2 cup tequila
1 clove garlic minced
or pinch of instant garlic
2 teaspoons dried oregano
2 teaspoons cumin seeds
or 1/2 teaspoon ground cumin
salt and coarsely ground pepper to taste

In a nonstick roasting pan prepared with cooking spray, arrange turkey, skin side up. Bake, unseasoned in a preheated 425-degree oven for 20 to 30 minutes, until skin is crisp. Drain and discard melted fat.
Spread onions under turkey. Combine remaining ingredients and pour over turkey. Lower heat to 350 degrees. Cover and bake for 1 hour or until turkey is tender. Uncover and bake until skin is crisp and liquid is reduced to a thick glaze. Baste frequently with pan liquid. (If needed, add a tablespoon of water.)
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