Add the butter to a small saucepan over medium heat. Let it melt fully, but don’t let it turn brown.

Stir in the minced garlic and cook for 30 seconds until it smells fragrant. Then whisk in the flour, salt, pepper, and oregano until smooth.

Slowly pour in the milk while whisking. Keep whisking until the sauce looks smooth and creamy.

Keep cooking over medium heat, whisking now and then, until the sauce thickens. This takes about 4–5 minutes. It’s ready when it coats the back of a spoon.

Take the pan off the heat and stir in the Parmesan cheese. Mix until it melts and blends into a smooth, creamy sauce.

Use the sauce right away on your pizza. If saving for later, let it cool and store in the fridge. It will get thicker as it cools, which makes it perfect for spreading.