In a bowl mix the dry ingredients: flour, sugar, salt, baking powder and lemon zest.
Add the butter cut into cubes to the mix and combine.
Then add the vanilla and water, and mix until it forms a ball that is just about smooth (make sure not to overwork it!).
Cut the dough in two a larger piece for the bottom and a smaller piece for the top. Roll them into 2cm disks and cover with clingfilm and refrigerate for 2 hours or overnight.
When ready, pre heat your oven to 170C.
Roll the dough disks to 5-6 mm, grease a 23 cm diameter tin and cover with the bottom piece of dough.
Fill the shell with jam, then cover it with strips of dough, and place them like a lattice on top. Chill for 10 minutes.
Bake for 35-40 minutes and cool completely before serving. Enjoy your vegan crostata on its own or with a cup of tea!