1. Place the baking sheet on the bottom part of the springform pan so that the sheet stays between the edges and the bottom part when you close the pan. Butter the edges of the pan that are not coated with the baking sheet.

2. Tip flour, vanilla, powdered sugar and salt into a mixing bowl. Add soft butter. Using your fingertips, press the dough evenly but be careful not to knead the dough so that it becomes sticky. Continue until it looks like a solid dough. Add a tablespoon of cold water if the dough feels too dry and hard to spread on the pan. Press the dough straight to the pan – you can roll out the dough and spread it evenly in the pan, or press it thin and even by hand. Put it in the freezer for at least 10 min. If you are planning to bake the tart crust immediately, turn oven to 170 C / 340 F.

3. Remove the pan from the freezer and trim any excess dough from the edges with a paring knife or press them down with the tines of a fork. Prick the dough on the bottom all over with a fork. Bake for 15-20 minutes, until golden. If the tart starts to bubble and rise from the middle, open the oven and prick couple of more holes with a fork. Remove from oven and let the crust cool to room temperature.

4. Start preparing the lemon filling by putting all ingredients on a large saucepan except the butter and lemon zest. Cook on medium heat and gently whisk at the same time, until the mixture begins to bubble and looks thick. Remove from the heat and stir in the butter and lemon zest until completely melted and incorporated. Taste and add more vanilla or lemon zest, and maybe a pinch of salt to balance the flavour. Pour the filling directly into the cooled pie crust. Let cool completely.

5. To make the meringue, measure the water and 300 g of sugar on a large saucepan. Boil the mixture to 121 C / 250 F. Add the egg whites to a bowl of a stand mixer fitted with the whisk attachment. Start whisking the egg whites on slow speed and gradually add 30 g of sugar. Increase the speed and whip until soft peaks. Continue whisking on full speed and slowly start pouring the hot sugar syrup into the egg white bowl while whisking – be careful that no syrup touches the whisk part. Continue whisking full speed until the mixture has cooled to 40 C / 104 F – measure with a thermometer.

6. Place the meringue on a strong piping bag and pipe it on the top of the lemon filling. You can also spoon over the meringue if you like a more simple look. Be careful to leave some space between the edges of the cake crust and the meringue. Burn the meringue slightly on the top with a chef’s torch or bake the tart of very high heat for 2-3 min. Decorate with berries, flowers or leave it as is.