1. Bring the beetroot juice to the boil in a small saucepan, then reduce the heat to low and simmer for 30 minutes until it begins to thicken and reduce by two-thirds. Remove from the heat and allow to cool.
2. To make the pastry, combine the almond meal, flour, baking powder, vanilla seeds, sugar, a pinch of salt and butter in a food processor and blitz until the mixture comes together as a ball of dough. Shape into a disc then wrap in cling film and place in the fridge to rest for 30 minutes. Preheat the oven to 170°C. Grease an 18cm x 18cm baking tin and line two baking trays with paper.
3. Roll out the dough on a lightly floured surface until 3 mm thick and use to line the prepared tin. Do not be too concerned about perfecting the pastry lining around the edges of the tin as later we will cookie cut the chocolate and pastry so you can see the two layers.
4. Place a sheet of baking paper on the pastry and top with baking beads or uncooked rice orlentils. Blind-bake for 10–15 minutes until golden brown. Remove from the oven, allow to cool.Reduce the oven temperature to 140°C.
5. To make the chocolate crémeux, whisk the egg yolks and sugar in a bowl until pale and thick. Combine the cream and milk in a saucepan and bring just to the boil. Turn the heat down until the cream mixture is just simmering. Pour one ladle of the hot cream mixture into the egg yolks, whisking constantly. Repeat this process twice more. At this stage you have tempered the egg mixture and you can now incorporate the sweetened egg yolks into the cream. Slowly pour the yolk mixture into the hot cream, whisking constantly. Continue to whisk over the heat until the mixture thickens and coats the back of a wooden spoon. Place the chocolate drops in a large bowl and pour on the hot custard. Stir constantly until all the chocolate has melted. Allow to cool. Pour the crémeux onto the pastry. Refrigerate for 2 hours to set.
6. To make the milk crunch, in a large bowl, combine the flour, milk powder, oat bran, butter, sugar and salt. Using your fingers, rub all the ingredients together until you have a rustic crumb-like texture. Sprinkle the milk crumble evenly over one of the prepared baking trays. Bake for 3 minutes, stir and shuffle the tray, then return it to the oven and repeat 3 times until you have a golden crumb. Allow to cool. Melt the white chocolate in a heatproof bowl over a saucepan of simmering water. Pour over the crumb, stir to combine and then freeze until set. Break into small clusters and return to the freezer. Reduce the oven temperature to 110°C.
7. Lay the beetroot peelings in a single layer on the remaining prepared baking tray. Sprinkle with the sugar and bake for 35–45 minutes until the crisps shrivel and begin to curl at the edges. Allow to cool and crisp.
8. Divide the cream between two bowls. Whip one to soft peaks with the vanilla seeds and the other to soft peaks with 2 teaspoons of beetroot reduction. Spoon both creams into piping bags and place in the fridge until required.
9. Press an 8cm cookie cutter into the crémeux and pastry, then carefully push the tart up and through the cutter and place in the middle of a serving plate. Repeat so that you have four tarts. Pipe one small swirl of the vanilla cream on each tart and then pipe on two large beetroot cream swirls. Top with the beetroot crisps and surround the tart on one side with the milk crunch.