For the lemon curd, dissolve the cornflour in 45ml (3 tbsp) coconut milk. In a small pot, whisk together the fresh lemon juice, the remaining coconut milk and the castor sugar. Bring to a boil over medium heat, stirring constantly, 6 minutes. Add the lemon zest and cornflour mixture and stir continuously while simmering until it thickens, 2 – 3 minutes. Allow to cool completely. Tint the curd yellow, if desired. Spoon into a piping bag.

Preheat the oven to 220˚C (or 200˚C for fan-assisted ovens). Line 3 large baking trays with baking paper. Roll the pastry out on a floured surface and cut into 3 equal pieces.

Place each pastry rectangle on a lined baking tray. Dust heavily with icing sugar. Place a sheet of baking paper over each pastry rectangle and place a large baking sheet on top. Bake the pastry sheets, 15 – 20 minutes, or until crisp and golden brown. Set aside to cool. Once the pastry has cooled, cut 6 rectangles (12cm x 5cm) from each sheet of baked puff pastry, so as to be left with 18 pastry rectangles.

For the meringue, place the chickpea brine in a saucepan and bring to a simmer. Reduce the brine until left with 125ml (½ cup) liquid, about 10 minutes. Set aside to cool down completely.

To assemble, place the cooled brine in the bowl of an electric stand mixer with the cream of tartar and vanilla extract. Beat until the mixture turns foamy and starts to form soft peaks. At this point, slowly add the 70g icing sugar, 60ml (4 tbsp) at a time. Continue to whip the mixture until it reaches stiff peaks. Place in a piping bag fitted with a star- or plain nozzle. Set aside 6 pastry rectangles (these will be the tops).

Spread a thin layer of raspberry jam over the remaining pastry rectangles. Snip the end off the piping bag with the lemon curd and pipe a blob in a corner of one of the pastry rectangles. Alternate the curd blobs with raspberries and continue piping curd with alternating raspberries until the pastry is covered. Sprinkle with the chopped pistachios. Repeat these steps with the remaining pastry rectangles.

Stack the rectangles on top of one another to have 6, double-layered pastries, topped with raspberries and lemon curd. Pipe the meringue onto the top layer of your mille-feuille. Toast the meringue with a kitchen blowtorch until golden (or briefly place it under a preheated grill, set on the highest setting if a blowtorch is not available).