Cook pasta according to package directions, drain. In a large saucepan over medium heat, melt butter.
Cook minced garlic in butter until fragrant. Add flour and cook for another minute to brown. Add in milk, salt, pepper, cheddar cheese, mozzarella cheese and parmesan cheese.
Continue to cook over medium heat, while whisking constantly. Cook until cheeses have melted and the sauce has thickened. Mix sauce with cooked pasta.