Cook Pasta: Boil pasta in unsalted water until al dente. Drain and set aside.
Make Cheese Sauce: In a saucepan, melt butter over medium heat. Add garlic and onion powders. Gradually whisk in milk. Slowly add cheeses, stirring until creamy.
Combine Pasta and Sauce: Add cooked pasta to the sauce and stir until evenly coated.
Optional Baking: Transfer to a greased baking dish, top with breadcrumbs, and bake at 350°F (175°C) for 15 minutes until golden brown.
Serve: Garnish with fresh herbs or extra cheese if desired.