1. Prepare tortellini according to package directions.
2. Meanwhile, snap off and discard tough ends of asparagus. Cut asparagus into 2-inch pieces.
3. Sauté onions in hot oil in a large skillet over medium heat 1 to 2 minutes or until softened. Increase heat to medium-high, add asparagus and bell pepper, and sauté 5 to 6 minutes.
4. Stir in pesto. Cook, stirring occasionally, 2 to 3 minutes or until thoroughly heated. Remove from heat; stir in pasta, and sprinkle with Parmesan cheese and, if desired, sliced black olives. Serve immediately.
Chicken and Pasta With Vegetables: Substitute 1/2 (16-oz.) package farfalle (bow-tie pasta) for tortellini. Cut 1 lb. chicken breast tenders into bite-size pieces, and sprinkle with 1 tsp. salt and 1/2 tsp. freshly ground pepper. Saute chicken in 2 Tbsp. hot oil in a large skillet over medium-high heat 6 to 7 minutes or until done. Proceed with recipe as directed, stirring in chicken with pasta in Step 4. Prep: 15 min., Cook: 18 min.