Zest the lemons. If you have a food processor handy I like to pulse the lemon zest and sugar together to really extract all the oils from them but this step is not a must.
Juice the lemons until you have about half a cup of lemon juice. Don't forget to strain out the seeds.
Strain egg yolks into a pot and beat lightly with a wire whisk. Whisk in the sugar and give it a good mix until lighter in color. Stir in lemon juice gradually.
Heat on low, while stirring constantly with a wire whisk until mixture thickens, just starts to bubble and coats the back of wooden spoon.
Remove pot from heat, then add the cold, cubed butter and mix until melted.
This is optional but I like to strain the final mixture to remove any bits of zest, etc. The final curd will be SILKY SMOOTH and amazing.
Transfer the curd to a sealable container or bowl. If storing in a bowl make sure to cover the surface with plastic wrap to prevent a skin from forming.
Video
Notes
The curd will set completely in the fridge. The lemon curd will thicken as it cools, so it’s really important to cool it completely before using it to fill cakes, or it won’t be the right consistency. I prefer making my lemon curd at least a day or two before I plan to use it. This way, I’m not rushed or waiting for it to cool.
How To Store Lemon Curd: Keep the lemon curd refrigerated in an airtight container for up to 1 week. Once it has fully cooled, you do not need to keep plastic wrap pressed to the surface, as long as it has an airtight lid.