Whisk all of the ingredients except butter in a medium saucepan until combined. Cook over medium heat, whisking constantly, until the mixture reaches 170°F.
Strain the mixture through a fine mesh strainer.
Refrigerate lemon curd for at least 1 hour and serve.
1 cup white granulated sugar
3/4 cup fresh lemon juice
2 tbsp lemon zest
1/4 tsp fine sea salt
2 large eggs
4 large egg yolks
6 tbsp unsalted cold butter, cut into small pieces
Remove the pan from the stove and immediately add in the butter. Whisk until melted and combined properly.
Then transfer the spread to a heat-safe bowl. Press a layer of parchment wrap directly onto its surface.