Add 1 tablespoon of butter into a small sauce pan and place over medium heat
Once the butter has melted, whisk in 1 tablespoon of all purpose flour and cook, whisking continuously, for about 30 seconds
Slowly whisk in 2/3 cup of whole milk
Add 2 pasted cloves of garlic and a pinch of salt and black pepper
Cook over medium heat for another 60 seconds or so, whisking continuously until the sauce begins to thicken a bit
Add 1/3 cup of grated parmesan and remove the sauce pan from the heat
Whisk the sauce until the parmesan has been fully incorporated
Add to cooked pasta or allow the sauce to cool a bit and use as a white pizza sauce