Macaroni Lasagna with Veggies and Dip

Name: Macaroni Lasagna with Veggies and Dip
Ingredients: Water, as needed; 1 pound extra-lean ground beef; 3 tablespoons frozen chopped onions; 1 teaspoon Italian seasoning; 1 teaspoon crushed red pepper flakes; 2 to 2 1/2 cups whole wheat macaroni; 1/2 cup low-fat mayonnaise; 1/2 cup low-fat sour cream; 1/2 teaspoon supermarket-style garlic and herb seasoning mix; 1 1/2 pounds precut mixed vegetables (about 6 cups celery, cauliflower, broccoli, and carrots); 1 (24 to 28-ounce) jar of your favorite pasta sauce; 2 cups grated low-fat cheddar