Rub the butter with the flour, icing sugar and ginger until the consistency is like breadcrumbs

Add the egg and mix with your hands till it forms a soft dough. Wrap in cling film and chill in the fridge for 20-30mins.

While that is chilling, toss the rhubarb, sugar and zest in a bowl and tip into an ovenproof dish. Bake in the oven at 160 for about half an hour until the rhubarb is just tender (about 15mins?) drain the water away and leave aside to cool.

Turn the oven up to 180. Roll out the pastry on a floured surface and carefully transfer it to a loose-bottom pastry tin. (Butter the tin first). Prick the base with a fork and pop back in the fridge for 20mins.

When the base has chilled, put on top a layer of baking paper with baking beans (or dried rice/beans/lentils and bake in the oven for 15-20 mins

When the pastry has been blind baked, discard the paper and leave to cool a bit while you make the meringue

Whisk the egg whites to soft peaks. Then carefully tip in half the sugar, continuing to whisk. Then whisk in the cornflour and finally the rest of the sugar until it’s smooth and glossy.

Spoon the rhubarb into the pastry case and then layer on a big dollop of meringue to cover. With the rest you can pipe it through a piping bag and pipe peaks all over the top (or just keep spooning on if you don’t have a piping bag!)

Bake in the oven for 20-30mins until the meringue is starting to go golden