What worked for me: change the way you label food in your head
This may not work for everyone, but it's a tip worth noting. Change the way you label food in your head. Instead of "this is something I really want" think of it as "this is just fuel that happens to taste good". Think of yourself as a machine that needs something to keep running. That something is fuel, no different from the ugly gasoline, it just happens to feel nicer. It's not food, it's not something desirable, it's just another one of your machine's requirements.
Dehumanize the food. Stop thinking of it as something personal, as something YOU really want, and see it as a mere tool. It's not for you, it's for "the machine". Is the machine running? Well, then it doesn't need more fuel yet apparently.
I find easier to stop caring so much about things/craving them when I don't think about them as personal desires to pursue.