Makes 1 cup curd. Recipe is by Teresa B. Day.
3 egg yolks
½ cup sugar
1 tablespoon lemon zest
1/4 cup lemon juice
4 tablespoons butter, sliced
1. Bring about one inch of water in the bottom pot of a double boiler (or use a saucepan) over medium heat to simmering.
2. In the top pot or a metal mixing bowl off the heat, whisk together the egg yolks, sugar, zest and juice, then place over the simmering water.
3. Cook, stirring frequently, until the mixture is thick enough to coat the back of a spoon, about 8 minutes.
4. Remove from heat and add butter one tablespoon piece at a time stirring until each tablespoon is melted before adding the next one.
5. Once cooled, store in small jars in the refrigerator for up to three weeks.