10Tablespoonsunsalted butter, cut into small cubes
Fit a fine mesh strainer over a large, heatproof bowl. Set aside until needed.
Fill a medium pot one-third full with water and bring it to boil. Once it's at a boil, reduce the heat to low and place a heatproof glass bowl (one that will fit on top of the pan snugly, but will not touch the simmering water) on top of the pan.
In the glass bowl, combine the lemon juice, zest, sugar, eggs, yolks, and salt; whisk until well combined. Stir in the cubes of butter and cook over low heat, whisking frequently, until the lemon curd is thick and creamy, about 15 minutes. Remove from heat.
Strain the lemon curd into the prepared bowl. Cover the bowl with saran wrap, pressing it down so it touches the surface of the lemon curd. Refrigerate for at least 2 hours before serving.
Store in an airtight container, in the fridge, for up to 1 week.