Feared Consequences — Decatastrophizing
Name the prediction, test the prediction

Every food rule and behavior is defended by a feared consequence: "if I eat this, I'll gain 10 pounds by morning," "if I stop weighing, I'll spiral," "if I have dessert, I'll never stop." Naming the prediction — and then actually testing it — is how the rules dissolve.
The disorder is a bad forecaster
ED predictions almost never come true, and when something like them does, it is smaller and shorter than the disorder promised. Every completed test weakens the next prediction.