1. Heat butter in a large skillet over medium heat; cook and stir onion, red bell pepper, and garlic until tender, 5 to 10 minutes. Stir in flour until dissolved and thickened, about 5 minutes. Pour in milk, stirring constantly, until well mixed. Add Parmesan cheese; stir until cheese is melted, 5 minutes. 2. Stir tomato sauce into creamy onion mixture; season with black pepper, balsamic vinegar, and hot sauce. Cook and stir until heated through, 5 to 10 minutes. Sprinkle spinach over sauce to serve. ---------------------------------------------------------------------------
Nutrition
Ingredients
