Cook Macaroni: Boil 2 cups of elbow macaroni until al dente, then drain and set aside.
Make Cheese Sauce: In a saucepan, melt 2 tbsp butter, stir in 2 tbsp flour to make a roux, then gradually whisk in 1 cup milk. Cook until thickened, then add 2 cups of shredded cheddar cheese. Season with salt and pepper.
Combine with Macaroni: Stir cooked macaroni into the cheese sauce until well coated.
Preheat Oven: Set oven to 375°F (190°C) and grease a mini muffin tin.
Fill Muffin Cups: Spoon mac and cheese mixture into each muffin cup, pressing down gently.
Add Toppings: Top each mac and cheese cup with pizza sauce, shredded mozzarella cheese, and grated Parmesan cheese.
Add Optional Toppings: Customize with toppings like diced cooked bacon, chopped pepperoni, sliced black olives, or diced bell peppers.
Bake: Bake in the preheated oven for 12-15 minutes, until cheese is melted and bubbly, and edges are golden brown.
Serve: Let cool slightly, then remove from muffin tin and serve warm as a delicious appetizer or snack.