50g lactose free butter, softened, plus extra for greasing
200g caster sugar
zest 2 lemons or 2 limes or 1 grapefruit
100ml lemon, lime or grapefruit juice, or a mixture
3 large egg, separated
50g gluten free self raising flour
250ml lactose free milk
icing sugar, for dusting (optional)
Method
Heat oven to 180C/160C fan/gas 4. Grease a medium-sized oval baking dish (we used 22 x 18cm) with lactose free butter.
Combine the lactose free butter, caster sugar and zest in a food processor and whizz until the mixture is pale.
Add the citrus juice, egg yolks, gluten free flour and lactose free milk, and whizz until well mixed – it may look a little curdled. Scrape into a bowl. Boil the kettle.
In a large, clean bowl, whisk the egg whites until firm but not stiff, then gently fold into the zesty mixture.
Scrape into the baking dish and put in a roasting tin half-filled with hot water from the kettle.
Bake for 35-40 mins until the top is lightly browned and set, but the pudding is still soft-ish underneath. Serve dusted with icing sugar, if you like.