Cut peppers in half lengthwise; remove seeds and membranes. Cook in boiling water, 5 minutes; drain well. (Or, microwave in 13x9-inch glass baking dish covered with plastic wrap 5 minutes on HIGH.)
In large skillet, brown ground beef, onion and garlic; drain. Remove from skillet; set aside.
In same skillet, prepare Rice-A-Roni Mix as package directs.
Heat oven to 375°F. Place cooked peppers cut-side up in 13x9-inch glass baking dish. Combine rice and beef mixture; spoon into pepper halves. Combine tomato paste, water and brown sugar; spoon over rice mixture.
Tent with foil; bake 25 to 30 minutes or until heated through. Sprinkle with cheese, if desired.
Calories 440, Calories from Fat 162, Total Fat 18g, Saturated Fat 6g, Cholesterol 50mg, Sodium 975mg, Total Carbohydrate 47g, Dietary Fiber 4g, Protein 21g, Vitamin A IU, Vitamin C mg, Calcium mg, Iron mg, Vitamin E mg, Folic Acid mcg