Step 1

In a medium saucepan, add in the lemon juice, zest and sugar. Bring to a simmer.

Step 2

Mix a little hot lemon juice with the cornflour, whisk and add it back into the saucepan.Whisk well.

Step 3

Reduce heat to low. Add whole egg and remaining egg yolks and butter. Cook for 3 minutes or until thick.

Step 4

Pass through a sieve to take out zest and any cooked egg. Put into a clean bowl and cover surface with a butter paper (or rub with a little butter and cling film). Set aside to cool.

Step 5

Store in the fridge for 2 weeks.