Cut up the vegan butter into cubes and add to a mixing bowl along with the flour.
Rub the vegan butter and flour between your fingertips until you have a mixture that resembles breadcrumbs.
Add the plant milk a few tbsp at a time until the pastry comes together into a ball of dough.
Wrap the pastry in cling film and leave to rest in the fridge for 30 minutes.
While the pastry is resting, pre-heat your oven to 150C.
Dust the work surface with flour, put the dough in the middle and sprinkle it with flour.
Flour your rolling pin then roll out the pastry into a circle 5cm/2” larger than the quiche tin.
Carefully lift it into the tin and push it into the corners and grooves.
To cut off the excess pastry, roll the rolling pin over the top of the tin.
Prick the bottom of the pasty with a fork.
Scrunch up baking paper then place inside the pastry case. Top the baking paper with baking beans.
Bake in the oven for 20 minutes or until beginning to go a pale golden colour.
Remove the baking paper and baking beans and bake for another 5 minutes until golden.
While the pastry case is baking, make the frangipane.
Whisk together the melted vegan butter and the sugar then whisk in the flour and cornflour followed by the aquafaba.
Next mix in the ground almonds, baking powder and almond extract and vanilla paste.
Cut the greengages in half and remove the stone.
Remove the pastry case from the oven.
Spoon in the frangipane.
Press the greengages into the frangipane along with the blackberries.
Scatter over some flaked almonds.
Place back into the oven and bake for 30 minutes.
Leave to cool slightly before removing from the tin and serving.