- 1/4 cup fresh lemon juice (usually requires 1-2 lemons)
- 2 teaspoons finely grated lemon zest
- 1/3 cup sugar
- 4 egg yolks
- 3 Tablespoons unsalted butter
1. Combine all ingredients in the top of a double boiler (or in a metal bowl over a pot of simmering water).
2. Heat, while stirring (almost) constantly with a whisk, until mixture thickens. It is done when it’s thick enough to coat the back of a spoon.
3. Remove from heat, cover and refrigerate until cool.
4. Store in the refrigerator up to 2 weeks.