Apple Lemon Curd

450g Apples, peeled, cored and chopped
Finely grated zest and juice of 2 unwaxed lemons (you need 100ml strained juice)
125g unsalted butter
450g granulated sugar
4–5 large eggs, well beaten (you need 200ml beaten egg)

Makes 5 x 225g jars

Put the chopped apples into a pan with 100ml water and the lemon zest.  Cook gently until soft and fluffy, then either beat to a puree with a wooden spoon or rub through a nylon sieve.

Put the butter, sugar, lemon juice and apple puree into a heatproof bowl over a pan of simmering water. As soon as the butter has melted and the mixture is hot and glossy, pour in the eggs through a sieve, and whisk with a balloon whisk. If the fruit puree is too hot when the beaten egg is added, the egg will "split". Check the temperature with a sugar thermometer — it should be no higher than 55–60C when the egg is added. If your curd does split, take the pan off the heat and whisk vigorously until smooth. Stir the mixture over a gentle heat, scraping down the sides of the bowl every few minutes, until thick and creamy. This will take 9–10 minutes; the temperature should reach 82–84C on a sugar thermometer. Immediately pour into jars and seal.

Use within four weeks. Once opened, keep in the fridge.