Mix the rhubarb with 70g (2.4 oz) of the sugar, and the orange zest and juice. Scatter in a roasting tray and roast for 20 minutes until soft.

Purée the rhubarb and its juices in a food processor, then pass through a sieve, pushing the rhubarb through with a wooden spoon into a pan to extract as much as possible*.

In a small bowl, mix the remaining sugar with the cornflour and enough of the rhubarb purée to make a paste. Return to the pan containing the rest of the rhubarb. Bring to the boil, bubble for a minute (this activates the cornflour), then remove from the heat. Taste and, if it’s too tart, add 1 tbsp more sugar.

Mix the egg yolks with the butter, then stir into the rhubarb mixture to make a curd. Scrape into a bowl, cover, cool and chill.

Put the coconut into a food processor with 1 tbsp of the flour. Pulse to a fine mixture. Mix with the rest of the flour in a large bowl and stir in the sugar. Add the cubed butter and, using your fingertips (or a pastry cutter), rub into the flour until the mixture resembles fine breadcrumbs. Add just enough iced water to bind. Knead briefly until smooth, wrap in cling film, then chill for 20 minutes (or if making ahead store in fridge).

Preheat oven to 200°C (400°F).

Take the pastry out of the fridge. Roll out the pastry on a lightly floured surface – the dough is a bit tricky to work with and easily sticks to the rolling pin – either ensure your rolling pin is lightly floured, or lay a piece of baking paper over top of the dough and then roll it out. Use the pastry to line a 20cm x 3.5cm (8 inch x 1.3 inch) fluted loose-bottomed tart tin.** If the pastry cracks or tears, simply patch it up using extra bits of dough. Chill for 30 minutes in the fridge. (NB: I allowed the dough to drap over the sides of the tin and baked it that way. Once fully baked, and while still warm, I trimmed the edges with a sharp paring knife).

Line the pastry case with baking paper and baking beans or rice and blind-bake for 12 minutes on the baking sheet, then remove the paper and beans/rice and bake for 5 minutes or until crisp and golden. Set aside.

Turn the oven down to 190°C (375°F).

Pour the rhubarb curd into the pastry case and bake for 30 minutes until set. Cool completely, then chill***.

Preheat oven to 190°C (375°F). Bring the chilled tart out of the fridge and bring to room temperature.

Whisk the egg whites until stiff, add 1 tbsp of the sugar, then whisk until stiff again. Add the remaining sugar in this way. Fold through the coconut and spoon the meringue over the rhubarb curd to form pretty peaks.

Bake in the oven for 15 minutes until the meringue is golden and crisp on the outside. Remove, cool and serve.