This curd recipe works well with any citrus fruit — lemons, limes, grapefruits. Plus it makes enough to fill a whole 9-inch tart, six 6-inch tartlets (see my Perfect Pastry recipe), or you can simply jar it and store it in the fridge for later. The balance of the sour-sweet-buttery flavors of this simple citrus curd can lend itself nicely to both sweet and savory dishes (or, hey, just spread it on some toast). Try my Angel Food Curd Cupcakes!