Start by shredding your cheeses and divide in half. Set aside.
Get your salted pasta water boiling and add your pasta. *It is important to cook your pasta for a few minutes less than the instructions say for it to be al dente. It will continue to cook in the oven.*
In a skillet, melt one stick of butter over medium heat, then add in your garlic. This only needs to cook for about a minute. Stir until the garlic is fragrant.
Whisk in the flour and stir continuously for about 3-4 minutes to cook out the raw flour taste. Stir in your seasonings as well. You should have a nice smooth roux after this.
Pour in the half and half and again stir it continuously for about 5-7 minutes until the sauce has thickened up.
Add in the 4 oz of cream cheese and HALF of the shredded cheeses. Stir until all the cheese is completely melted and you have a nice, thick creamy sauce.
Preheat oven to 400 degrees.
Grease a 9x13 baking dish, add in your cooked and drained pasta then pour the cheese sauce in and mix it really well.
Bake for about about 15 minutes. Turn the oven to broil and cook for another 5 minutes. Oven times vary so keep a close watch on it so it doesn't burn.
Remove from the oven and let cool for at least 10 minutes to allow it to thicken up a bit.