Lemon Curd

Place the sugar in a medium bowl, then zest the lemons directly over the top. Use your fingers to rub the zest into the sugar until the sugar is damp and fragrant, about 30 seconds. 

In a medium, heavy bottomed saucepan over low heat, heat the lemon juice until it’s hot but not boiling. 

Meanwhile, in a medium bowl, whisk together the eggs and egg yolks until very well-combined. Add the sugar to the eggs in three additions, whisking well between each.  

Place a fine-mesh sieve over the medium bowl that was used for the sugar and set aside. 

While whisking constantly, gradually stream the hot lemon juice into the egg mixture. Pour the mixture back into the saucepan and place over medium heat. Whisk constantly, being sure to reach the edges of the pan, until the mixture is thickened enough to coat the back of a wooden spoon or flexible spatula and registers 170°F on an instant read thermometer, 6 to 8 minutes. 

Immediately pour the curd through the fine-mesh sieve and into the bowl below, scraping the bottom and sides of the saucepan as needed. Add the cold butter, vanilla, and salt and whisk vigorously until the butter is incorporated and the mixture is glossy.  

Press a piece of plastic wrap directly against the surface of the curd. Refrigerate until set, about 4 hours, and then use as desired. 

Store lemon curd in an airtight container in the refrigerator for up to 1 week. Freeze for longer storage.