Lemon curd is a sweet sauce made by cooking lemon juice with butter, egg yolks and sugar in a nonreactive double boiler or saucepan. The thickened, cooled mixture is used as a filling for cakes and tarts, or it can also be spread on scones, a tradition we get from the English. It can also be paired with a piece of gingerbread of a slice of pound cake.
Use a heavy-based, nonreactive saucepan to cook, and stir often to keep the sauce creamy and to prevent burning. Don’t let the curd boil. To avoid straining cooked egg pieces, try preparing this way: mix the ingredients as if making a cake; cream the butter and sugar until fluffy, beat in the eggs slowly, then add the lemon juice. Get the recipe for this method.
Tightly covered, lemon curd will last about a week in the refrigerator. Or it will last months tightly covered in the freezer. It doesn’t freeze solid, allowing you to spoon out exactly what you need when you need it.