Separate the yolks from the whites and save the whites for another recipe.

Zest 6 lemons and measure out ¼ cup of zest.

In a food processor, blend the sugar and the lemon zest until the sugar is a fine powder and the zest has infused the sugar.

With the food processor running, pour in the 1 cup of fresh lemon juice

Add the egg yolks, one at a time, allowing each one to incorporate fully.

While the food processor is still running, pour the melted and cooled butter into the yolk/lemon juice mixture.

Strain the mixture through a super fine mesh strainer to help remove any foam.

Fill half pint jelly jars with the lemon curd mixture.

Place a lid and ring on top of the jars and make the ring finger tight.

Heat the sous vide to 167 °F / 75 °C.

Once heated, carefully lower the jars into the water with a jar lifter. Make sure there is water completely surrounding the jars.

Cook for 1 hour.

Carefully remove from the water and allow to rest to cool to room temperature and then store in the refrigerator for up to 2 weeks.