If you don’t have a lemon on hand, you can use the zest of another other citrus fruit, such as a lime, orange, or grapefruit.

Lime zest is the best 1:1 substitute for lemon zest. You can also substitute orange or grapefruit zest for lemon zest. If you need lemon zest but find yourself with no citrus in the house ...

Go with the rosewater and lime flavour or swap in lemon or orange zest. Preheat the oven to 190C/170C Fan/Gas 5. Grease the sides of a 23cm/9in round cake tin and line the base with baking paper.