95gUnsalted buttercut into 2 cm cubes (6 tablespoons)
3Large eggs
1Large egg yolk
Here's what we do...
Create a bain marie - i.e. take your large saucepan and fill it about a third full with boiling water and allow it to simmer. Check that your heatproof mixing bowl will fit on the top without touching the water below.
Add your lemon juice and zest, your sugar and cubed butter to your heatproof mixing bowl and place it securely over the pan of simmering water.
Stir gently until the butter has melted.
Whisk your eggs and egg yolk together until incorporated and no egg white remains.
Pour your eggs into the melted butter mixture and keep stirring to be sure they mix in well. A balloon whisk works well for this.
Cook for 8 minutes, continually stirring, and then remove from the heat and put the curd through a sieve to remove the pieces of lemon zest.
Return the curd to the saucepan and continue to cook for another 5-7 minutes, stirring lightly to be sure that the curd cooks evenly.
By this point you should find that if you dip a dessert spoon into the curd, it will coat the back of it. That means the curd is done. If not, continue to cook for another couple of minutes.
Remove the bowl from the pan and set it aside to let it fully cool.
Once cool, give the lemon curd a stir and then pour it into a sterilised jar, seal and refrigerate.