If the puff pastry is frozen, from the evening let’s transfer it to the fridge so that it delicately unfreezes. Note that cream is measured not in milliliters, but in grams. Mix sugar with vanillin. Take the zest off the lemon on small grater.
Preparation of cakes begins with preparation of vanilla custard. It can be cooked on a water bath, which will significantly increase the time of dessert preparation. And you can cook it by putting a saucepan on the smallest fire and, stir constantly, control the process so that the custard doesn’t overheat.
So, in a saucepan with a thick bottom pour sugar with vanillin, add egg yolks and lemon zest.