Can I Use An Alternative To Branded Custard Powder For The Birthday Custard Sponge? | Ask Nigella.com (2024)

Our answer

Nigella's Birthday Custard Sponge (from FEAST) uses custard powder to give the sponge a golden colour and vanilla flavour. The custard powder also helps to make the sponge slightly more tender. Bird's custard powder is the type that is mixed with milk to make custard. We haven't been able to find another brand that is mixed with milk but if you do find one then you should be able to use it as an alternative.

However, be careful not to confuse Bird's custard powder with "instand custard mix" as this is mixed with boiling water to make custard and has a different combination of ingredients, which could affect the cake. Instead we would suggest replacing the custard powder with a combination of cornflour (cornstarch) and vanilla. For the sponge batter replace the 3 tablespoons of custard powder with 3 tablespoons of cornflour and 1 teaspoon of vanilla extract. For the buttercream replace the 4 teaspoons of custard powder with 4 teaspoons of cornflour and 1/2 teaspoon of vanilla extract. You can also add a couple of drops of yellow food colouring if you would like to give the sponge and buttercream a little more of a yellow tint, but do so a little at a time so that the colour is subtle rather than day-glo.