1. Cook the fettuccine according to the package directions.

2. Heat the milk and cream in a large, heavy saucepan until the mixture comes to a simmer.

3. Slowly whisk in the cheeses and then remove from the heat.

4. Place the egg yolks in a bowl and slowly whisk in a portion of the hot milk and cream mixture.

5. Slowly pour the egg yolk mixture back into the milk and cream mixture in the pan.

6. Season to taste with salt and pepper.

7. Add the cooked fettuccine to the saucepan. Sprinkle in the garlic powder and stir until the sauce thickens to the desired consistency.

8. Sprinkle with parsley. Serve immediately.