01 -
Soften the unsalted butter in the microwave, then set it aside so it can cool slightly.
02 -
In a medium-sized microwave-safe bowl, whisk the granulated sugar together with the eggs and the additional egg yolk.
03 -
Stir in the fresh lemon juice and lemon zest into the bowl with the sugar and eggs.
04 -
Slowly whisk the melted butter into the mixture until well combined.
05 -
Set the microwave to 50% power and heat the mixture for one minute. Remove and stir. Then, heat in one-minute intervals at full power, stirring between each, until it thickens enough to coat the back of a spoon.
06 -
Pour the thickened curd through a fine-mesh sieve to remove the lemon zest. Transfer into sterilized jars and store in the refrigerator for up to three weeks.