In a large pot, bring 4 cups of water to a rolling boil over high heat. Once boiling, add elbow macaroni and cook for 7–8 minutes until al dente. Drain and rinse under cold water.

Return the drained macaroni to the pot and add in 3 tablespoons of unsalted butter, gently stirring to melt.

Gradually pour in 1/2 cup of warm milk and add shredded sharp cheddar and mozzarella cheese. Stir continuously until cheese melts and creates a smooth sauce.

Season with salt, ground black pepper, and optional paprika. Mix well to combine.

Serve immediately, garnishing with additional shredded cheese or paprika if desired.