Cook pasta according to package directions; drain. Keep warm.
Meanwhile trim fat from beef Top Sirloin Steak. Cut steak lengthwise in half and then crosswise into 1/8-inch thick strips. In wok or large nonstick skillet, heat 1 to 2 tablespoons oil over medium-high heat until hot. Add beef and garlic, 1/2 at a time, and stir-fry 1 to 2 minutes or until outside surface is no longer pink. Remove from pan with slotted spoon; season with salt and pepper. Keep warm.
In same pan, heat 1 tablespoon oil until hot. Add mushrooms and bell pepper strips; stir-fry 3 to 4 minutes or until mushrooms are tender. Remove from heat. Return beef to pan; add sliced basil and toss.
Place pasta on large deep platter; arrange beef mixture on pasta. Sprinkle cheese over beef and pasta or pass separately, if desired. Garnish with basil sprigs and bell pepper rings.
Nutrition information per serving: 520 Calories; 144 kcal Calories from fat; 16 g Total Fat; 5 g Saturated Fat; 7 g Monounsaturated Fat; 93 mg Cholesterol; 518 mg Sodium; 47 g Total Carbohydrate; 3.3 g Dietary Fiber; 44 g Protein; 4.3 mg Iron; 15.2 mg Niacin; 0.9 mg Vitamin B6; 1.9 mcg Vitamin B12; 7.1 mg Zinc; 48.9 mcg Selenium; 137.9 mg Choline;