Desert good for vegetarians too!
Preheat the oven to 190°C/170°C Fan/Gas 5.
Line a 20cm Victoria sandwich tin with baking parchment.
Place the biscuits in a plastic bag and holding the end closed, crush with a rolling pin.
In a bowl lightly beat one egg white, add the crushed biscuits and mix well.
Transfer to the sandwich tin and press evenly over the base and up the sides using the back of a wetted spoon.
Bake in the oven for 10 minutes, then set aside to cool.
Place the lemon juice and rind in a saucepan.
Add 600ml water and whisk in the egg yolks.
Heat, stirring continuously, until the mixture starts to thicken, taking care not to let it boil.
Cook for a further 5 minutes. Remove from the heat and whisk in the jelly crystals and 4 tbsp artificial sweetener.
Set aside to cool completely, then pour over the biscuit base.
Chill for 2 hours until set, then carefully remove from the tin.
Whisk the remaining egg whites until they''re very stiff and dry.
Fold in the remaining artificial sweetener using a large metal spoon.
Pile on top of the lemon filling, making sure that it is completely covered.
Place the lemon pie on a baking sheet and place under a preheated hot grill for about 1 minute until golden brown.