Cook tortelloni according to package directions; drain and keep warm.
While pasta cooks, sauté garlic in hot oil in a large skillet over medium heat 3 minutes. Add red bell pepper and next 3 ingredients, and sauté 8 to 9 minutes. Stir in 1/4 cup water and salt and pepper to taste.
Toss together tortelloni, vegetable mixture, and cheese until blended. Serve immediately.
Tip: Cut vegetables ahead of time, wrap in damp paper towels, and place in a zip-top plastic bag. Chill up to one day.