Can you use granulated sugar instead of caster in sandwhich cakes?

You can use granulated sugar instead of caster sugar in a sandwich cake, but it might require some adjustments.

Here's why:

* Texture: Caster sugar dissolves more readily than granulated sugar. This means it can lead to a smoother, finer crumb in your cake. Granulated sugar might leave tiny crystals in the cake, resulting in a slightly coarser texture.

* Sweetness: Caster sugar is slightly finer than granulated sugar, so it may be a little sweeter. You might need to adjust the amount of sugar in your recipe if you're substituting granulated sugar.

* Creaming: Caster sugar creams more easily with butter, leading to a lighter and airier cake. Granulated sugar might be a little harder to cream, potentially impacting the overall texture.

Here's what you can do:

1. Pulse the granulated sugar in a food processor: This will help break down the sugar crystals, making it closer to the consistency of caster sugar.

2. Reduce the amount of sugar by 10-15%: This will compensate for the potential sweetness difference.

3. Cream the butter and sugar longer: Make sure you cream them thoroughly to help dissolve the sugar and ensure a smooth texture.

Ultimately, using granulated sugar is fine, but it might result in a slightly different texture and sweetness. If you have caster sugar, it's best to use that for the optimal result. However, if you only have granulated sugar, the adjustments above can help you make a delicious sandwich cake!