1. Bring a large pot of water to a boil. Add spinach and cook briefly to blanch (30 seconds). Drain spinach and run under cold water to cool quickly.
2. Cook pasta according to package directions.
3. While pasta cooks, puree together spinach, garlic, cottage cheese, milk in a food processor or blender until smooth. Stir in Parmesan cheese, basil, salt, and pepper.
4. Toss warm pasta with sauce and red peppers to serve.