Mixed Citrus Curd

Place sugar, butter, eggs, juices, zests, and salt in a 2-quart saucepan over medium heat. Cook, whisking constantly, until curd starts to bubble and thicken, and can coat the back of a wooden spoon, 8 to 10 minutes. Remove from heat and pour into a bowl. Place a piece of plastic wrap over the surface to prevent a skin from forming.n

Refrigerate curd until set, 2 to 3 hours.n