This twist on the classic lemon curd is perfect for anyone who (like me) adores grapefruit! It's great with meringues and berries, as a filling in a layer cake or tart, or even by the spoonful! The recipe makes a reasonably small batch so definitely double (or triple) it if you're cooking for a group. This quantity is perfect for a small tart or as dessert for a few people.
Simmer the grapefruit juice in a small saucepan until it’s reduced in size to ¼ of a cup.
In a small bowl combine the sugar and the grapefruit zest and rub the zest into the sugar.
Whisk the egg and egg yolk together in a second small bowl, add in the sugar and then stream in the warm grapefruit juice.
You can either set the bowl (if it’s heat proof) over a simmering pan of water and cook the curd in a bain marie. Or if you prefer you can pour the grapefruit and egg mixture into a thick bottomed pan and cook it directly over the heat. If you cook it directly in a pan it’ll cook much faster but you need to be a bit more careful to avoid overcooking it! Either way you should stir the mixture constantly until it thickens quite a lot. In a bain marie this can take close to 15 minutes so be patient and keep whisking until the mixture can coat the back of a wooden spoon such that if you draw your finger through the mixture you can see a clear path.
Once it’s thickened take it off the heat, stir in the butter and pour it into a jar. Refrigerate the curd until you’re ready to use it!
Notes
* Grapefruit has quite a bitter sharp flavor, personally I really like that but you may find this curd a bit too sharp. You can balance the sharpness a bit by increasing the sugar content by a tablespoon or two.** I always keep extra egg whites. You can store them in the fridge in a small Tupperware or jar for a few days or freeze them for a few months and then defrost them when you want to use them. They’re ideal for meringues or try out this apple cider donut recipe*** This curd is quite thick which is ideal for a tart but maybe less ideal if you want to use it as a sauce over berries. If you prefer a slightly thinner curd then decrease the butter content to 20 grams.