Cut a piece of parchment paper to fit inside a small saucepan. Butter the parchment paper and set aside. Whisk the eggs in a medium bowl and set aside. Combine the sugar, cornstarch and salt in small saucepan. Add lemon juice and butter to the saucepan to create a lemon mixture.
Bring to a simmer over medium-high heat. Whisk constantly and cook for 1 minute. Temper the whisked eggs by slowly whisking a small amount of the lemon mixture into the eggs. Repeat this until about half of the lemon mixture has been incorporated, then transfer the lemon and egg mixture back into the saucepan. Reduce heat to low and cook, whisking constantly, until curd has thickened, about 2 minutes, without boiling.
Transfer to a bowl and stir in the lemon paste. Cover the surface of the bowl with a piece of parchment that has been coated with a thin layer of butter. Refrigerate until completely cool, about 1 hour.
Cut a piece of parchment paper to fit inside a small saucepan. Butter the parchment paper and set aside. Whisk the eggs in a medium bowl and set aside. Combine the sugar, cornstarch and salt in small saucepan. Add lemon juice and butter to the saucepan to create a lemon mixture.
Bring to a simmer over medium-high heat. Whisk constantly and cook for 1 minute. Temper the whisked eggs by slowly whisking a small amount of the lemon mixture into the eggs. Repeat this until about half of the lemon mixture has been incorporated, then transfer the lemon and egg mixture back into the saucepan. Reduce heat to low and cook, whisking constantly, until curd has thickened, about 2 minutes, without boiling.
Transfer to a bowl and stir in the lemon paste. Cover the surface of the bowl with a piece of parchment that has been coated with a thin layer of butter. Refrigerate until completely cool, about 1 hour.
