How to make
Crumble the biscuits, add the lemon zest and pour on the melted butter. Mix everything well and transfer the mixture into a cake form 8 3/4″ (22 cm) in diameter with removable walls. Press firmly toward the bottom to make the base. Put the cake layer in the fridge for the butter to harden.
In the meantime, make the cream. Make a mixture of the egg yolks, flour, vanilla and 2/5 cup (100 ml) milk.
Heat the rest of the milk with the sugar and once boiling, add the mixture while stirring nonstop. Once it's ready, take it off the heat.
Soak the gelatin in water and leave it to swell for a few min. Then add it to the warm cream and stir very well. Pour the cream over the cooled base and leave it in the fridge to harden for at least 4-5 hours.
Take it out of the form by sliding a knife along the walls and serve the cheesecake with a jam of your choice poured over it.