Fill a large pot with water and add a generous pinch of salt. Bring to a boil.

Add noodles and cook according to package instructions until al dente (usually 8-10 minutes). Drain well using a colander and set aside.

While noodles cook, melt butter in a medium saucepan over medium heat. Stir in flour and cook for 1-2 minutes, whisking constantly, until lightly golden.

Gradually pour in milk, whisking continuously to avoid lumps. Cook for 3-4 minutes until the sauce thickens slightly.

Lower the heat and stir in cheddar, mozzarella, and Parmesan cheeses. Continue to stir until the cheese melts and the sauce is smooth. Add salt and pepper, adjusting to taste.

Combine the drained noodles with the cheese sauce in the saucepan or return them both to the pot. Toss until noodles are evenly coated.

Serve hot, garnished with extra cheese or freshly ground pepper if desired.