What you need to do:

Make the pastry by rubbing the butter and lard straight from the fridge into the flour until it resembles breadcrumbs. Add cold water and mix using a metal knife until the breadcrumbs form a dough. Wrap the dough in clingfilm and let it rest in the fridge for 30 minutes.

Wash and trim the rhubarb, cut into chunks and place in an open ovenproof dish. Grate the zest of the oranges onto the fruit and sprinkle the caster sugar on top. Bake in the oven at 190°C, 180°C Fan for 20 minutes.

Roll out the pastry and line the quiche tin, making sure the pastry overlaps the tin slightly as it will shrink back when cooked. Prick the base all over and brush with beaten egg. Put the tin on a baking-sheet and bake for 20-25 minutes, just until pastry is browning.

Squeeze the orange juice into a saucepan, reserve a little in a cup and add the cornflour to this. Stir the cornflour and orange juice together and then add to the saucepan. Bring this mixture up to simmering point and stir until it thickens. Remove from the heat, stir in the ground almonds and the juice of the cooked rhubarb. Put the saucepan back on the heat, continue to whisk and add the egg yolks. The mixture will become like custard in consistency. Remove from the heat and cool.

To make the meringue-topping, whisk the egg whites until they form stiff peaks. Add the caster sugar a spoon at a time until you have a very thick and shiny mixture.

To assemble the pie: pour the rhubarb and almond custard into the pastry case and then spoon the meringue mixture on top. Bake at the same temperature for 25 minutes, until the meringue is just beginning to brown.

And another thing...

This dish is best served the same day.