1/4 cup vegetable oil and 1/4 cup butter,1 1/2 cups chopped chicken breast,3 cups peeled, diced potatoes, 1 cup diced onions, 1/2 cup diced bell peppers, 2 Tablespoons prepared horseradish, 1-1 ounce package ranch dressing mix, 1 cup shredded sharp cheddar cheese, salt and pepper to taste.
Heat oil and butter over medium heat in a 12 inch non-stick skillet. Add chicken and stir-fry for 1 minute. Stir in remaining ingredients except cheese . Cover and cook, stirring occasionally, until vegetables are tender (15 to 20 minutes) Remove from heat. Drain excess grease. Sprinkle cheese on top, cover and let set until cheese is melted.