Set a medium saucepan with about 10cm of water on a medium heat and bring to a simmer. Place the pink grapefruit zest and juice, the sugar, butter and egg yolks into a large heatproof bowl and sit it on the pan of simmering water. Leave to cook and thicken enough to coat the back of a spoon, stirring occasionally. This should take 20-25 minutes.

Remove the bowl from the heat, press cling film directly on the surface to prevent a skin from forming and leave to cool.

Arrange the pastry cases on a large tray. Once cool, spoon the grapefruit filling into the cases to come just to the tops and set aside. These can be prepared a day in advance, keeping them chilled in the fridge until they are ready for topping and serving. Store in a baking tray that is deep enough to prevent a covering of cling film from sticking to the tops.

When ready to serve, prepare the meringue topping. Whisk the egg whites in a medium bowl with an electric mixer until soft peaks form. Add the sugar in a few batches, beating until it dissolves before adding the next, to give a smooth, thick and glossy meringue. Spoon the meringue into the piping bag.

Pipe the meringue generously on top of each pie in a decorative fashion to come nearly to the edge and to give about a 3cm- high peak. Use a blowtorch to turn the meringue evenly golden. Alternatively, give them a quick toasting under a hot grill. Arrange on a pretty platter or cake stand and serve immediately. Once topped, these are best eaten within the day.

This recipe is from my book, No-Bake Baking, available worldwide in all good bookstores and on Amazon.

Photo © Donal Skehan