Creamy White Pizza Sauce

Collect and prepare all necessary components.\nHeat the butter and olive oil in a small saucepan over medium heat; stir in the onion and garlic. Whisk the flour into the mixture until it becomes lightly browned and the onion is tender, approximately 2 minutes.\nAdd 1 cup of milk, Parmesan cheese, basil, oregano, salt, and black pepper to the saucepan. Continue to cook, whisking constantly, until the cheese is melted and the sauce has thickened slightly, around 5 minutes.\nIf the sauce appears too thick, add additional milk to achieve the desired consistency. Remove the saucepan from heat and let it cool down.