A balsamella (bal-sah-MEHL-ah) is a white sauce made from milk and flour. It's a staple of Italian cooking and is often used as a topping for baked pasta dishes. It adds creamy richness to this dish and keeps the pasta moist as it bakes.
1. Preheat oven to 425°.
2. Cook pasta according to package directions, omitting salt and fat.
3. While pasta cooks, remove casings from sausage. Heat a large nonstick skillet over medium-high heat. Coat pan with cooking spray. Add sausage and onion; cook until sausage is browned, stirring to crumble. Add bell peppers and garlic; cook 3 minutes, stirring frequently. Stir in marinara sauce; cover, reduce heat, and simmer 10 minutes or until peppers are tender.
4. Drain pasta, and return to pan. Add pepper mixture; toss gently to coat. Divide pasta mixture evenly between 2 (11 x 7-inch) baking dishes coated with cooking spray.
5. Place flour and salt in a medium saucepan. Gradually add milk, stirring with a whisk until well blended. Bring to a boil over medium heat, and cook 3 minutes or until thick, stirring constantly with a whisk. Remove from heat; stir in 1/2 cup cheese. Pour 1 cup white sauce over each casserole; sprinkle each with 1 tablespoon cheese. Bake at 425° for 20 minutes or until lightly browned and bubbly.
Freezer Friendly: This recipe makes two casseroles--enough for a crowd. Or serve one for a family meal and freeze the other for later. When you're ready, simply bake the frozen casserole, covered, at 425° for 30 minutes; uncover and bake an additional 30 minutes.