Melt butter in large skillet on medium heat. Add onions; cover. Cook 9 min. or until onions are tender, uncovering after 3 min. and stirring frequently. Stir in garlic; cook 8 to 10 min. or until onions are golden brown, stirring occasionally. Stir in 3 Tbsp. steak sauce and sugar; cook and stir 2 min.
Place chicken in shallow baking dish. Mix remaining steak sauce and mustard; spread over chicken. Top with onions.
Bake 30 min. or until chicken is done (165ºF). Serve topped with cheese and sauce from bottom of dish.
Serve with smart sides, such as a baked potato and your favorite steamed vegetable.
Tent chicken with foil if onion mixture becomes too brown before the chicken is done.
Calories From Fat
% Daily Value*
Total Fat 11g
Saturated Fat 5g
Trans Fat 0g
Total Carbohydrates 18g
Dietary Fiber 2g
* Percent Daily Values are based on a 2,000 calorie diet.
* Nutrition information is estimated based on the ingredients and cooking instructions as described in each recipe and is intended to be used for informational purposes only. Please note that nutrition details may vary based on methods of preparation, origin and freshness of ingredients used.