For the blackberry curd

Cook the blackberries and apples in a pan with enough water to just cover the fruit.

Bring to the boil and reduce the heat to a simmer and cover. Simmer the fruit for 20 minutes or until soft.

Remove the pan from the heat and pass the fruit through a fine sieve into a clean bowl.

Melt the butter in the pan used to soften the fruit and mix in eggs, lemon juice, sugar and blackberry and apple puree.

Whisk, while moderating the temperature for 15 to 20 minutes until the curd has thickened.

Pour into a bowl, cover with plastic wrap so that the plastic actually touches the curd; and refrigerate while you prepare the pastry.

For the pastry

Combine the flour and the butter in a bowl. Use a fork to mash until the mix resembles breadcrumbs.

Stir in water quickly and bring the dough together so that it forms a sticky ball. You may need to use more water than the recipe calls. If the dough isn't very sticky, add more water.

Wrap dough in plastic wrap and let rest in the fridge for 30 minutes.

Roll the dough out between two layers of greaseproof/baking paper.

Grease the tart tins well and press the dough into the tart tins, being sure to press along the sides.

Blind bake the cases at 340f/170c for 15 to 20 minutes or until starting to color.

For the meringue

Pour 40 ml of the water into a saucepan fitted with a food thermometer. Add the sugar and glucose and bring to the boil, stirring every now and then.

Start beating the egg whites in a stand mixer, when the water, sugar and glucose, reaches 230f/110c on the thermometer. Beat the egg whites until they form soft peaks.

Keep an eye on the sugar syrup and stop cooking it, the moment it reaches 250f/121c. Remove the saucepan from the heat and wait a few seconds while it stops bubbling.

Pour the syrup into the stand mixer ever so slowly while the whisk continues to beat.

Keep whisking the whites for 10 minutes after the all the syrup has been absorbed. When the outside of the bowl of the stand mixer is cool to the touch, the meringue is ready for use.

Fill a piping bag with the mix and pipe onto the filled pastry cases.

Burnish the peaks of meringue using either a cook's blowtorch or by letting the tarts stand under a hot grill/broiler for a few minutes.