In a saucepan or pot (not on the stove), beat eggs till frothy. Add sugar, lemon juice and zest. Whisk till mixed. Add in butter chunks, and place the pot on the stove over medium heat, stirring constantly so that the mixture does not curdle. It may look curdled because of the butter, but don’t worry- once the butter melts, it’ll all come together.

Bring the mixture to a rolling boil until THICK.

Strain the lemon curd into a bowl, cover the surface with cling wrap and chill overnight.