Baked custards set because egg proteins coagulate into a network that traps water and fat. Heating that network too aggressively makes it contract and expel moisture.
What matters technically
- Use moderate, even heat.
- A water bath can buffer rapid temperature change.
- Remove custards before residual heat pushes them too far.
Common mistakes
- Boiling the custard in the oven
- Overbaking until completely rigid
- Whisking excessive air into a mixture meant to bake smooth
My approach
I treat this as a formulation and process problem rather than a fixed recipe. Ingredient ratios, temperature, mixing, baking or setting conditions must support the texture and flavour required in the finished dessert.