MAKE THE PASTRY: Whisk the flour, sugar, and salt together in a large mixing bowl. Add the cubed butter and rub together using your fingertips until the mixture looks rough and pebbly. Pour in the water and vinegar, then use a table knife to mix into a loose dough. Turn out onto the bench and squeeze together into two discs. Wrap in clingfilm and refrigerate for 30 minutes.

ROLL OUT THE PASTRY: When the pastry has chilled, roll out one disc into a large round to fit your pie dish. Grease a 23cm / 9 in. diameter pie dish, lift the dough into the dish, and press gently down to fit and trim the edges. Scatter the ground almonds evenly over the base, then chill until needed.

PREPARE: Heat the oven to 180°C / 350°F / Gas 4 with an oven tray lined with baking paper (no mess!) in the bottom third of the oven.

MAKE THE FILLING: In a large mixing bowl, toss together the blueberries, sugar, vanilla, cornstarch and lemon zest. Pour into the prepared pie shell and return to the fridge.

ROLL OUT THE PASTRY LID: Roll out the second pastry disc on a floured surface, if you like, you can get creative, cutting into strips to weave a lattice top, or just leave it simple.

ASSEMBLE THE PIE: Place the pastry lid onto the pie and press the edges to seal, crimping to decorate. Cut a couple of air vents in the middle, brush with beaten egg and sprinkle with sugar. Bake in the preheated oven for 1 hour, until golden brown and bubbling.

COOL THEN SERVE: Allow to cool for at least 30 minutes before slicing and serving - this pie is delicious with a big scoop of vanilla ice cream!