Do not add flour directly to the sauce without making a roux first (butter + flour cooked together). Raw flour tastes like cardboard and feels like glue. You’ll be eating paste, and not the fancy edible kind from kindergarten.
Do not crank the heat to “hurry up” mode. High heat breaks the emulsion and turns your sauce into oily shards. It’s like trying to speed-date a soufflé—disaster guaranteed.
Avoid using pre-shredded cheese that comes in bags. Those bags have anti-caking agents (cellulose powder, aka wood pulp). Yup, your “cheese” has sawdust. It won’t melt properly, and your sauce will be grainy like a bad life decision.
