Blood orange tart with cardamom cream

Method

1. Finely grate the zest of 1 orange and set aside for the pastry. Peel 4-6 oranges (depending on their size), including the zested one, making sure you cut off and discard all the bitter pith. Thinly slice all the oranges.
2. To make the pastry, briefly pulse together the flour and 100g unsalted butter in a food processor until the mixture resembles breadcrumbs. Add 50g of the sugar, the grated orange zest, the egg yolk (reserving the white) and 1-2 tbsp iced water. Pulse again until the mixture just starts to come together. Transfer to a clean, lightly floured surface and gently work into a dough. Shape into a disc, wrap well and chill for 30 minutes (see Make Ahead).
3. Heat the oven to 220°C/200°C fan/gas 7. For the orange syrup, squeeze the juice from 2 oranges into a small saucepan, add the maple syrup or honey, then simmer over a medium heat for 5-6 minutes or until the sauce is syrupy. Set aside to cool.
4. Roll out the dough on a lightly floured surface to a rough 30cm circle, then transfer it to the prepared baking sheet.
5. Put the ground hazelnuts, 50g softened unsalted butter and the remaining 50g sugar in a mixing bowl. Using an electric mixer, whisk until pale and fluffy – about 6 minutes. Spread the mixture over the pastry base, leaving a 4cm border all around.
6. Arrange the sliced oranges, slightly overlapping, over the hazelnut mixture. Fold in the edges of the pastry to form a crust. Whisk the egg white until just frothy, then brush it over the pastry rim to glaze. Transfer the tart to the oven and bake for 25-30 minutes until the pastry is golden. Set aside to cool.
7. Just before serving, whip the cream, ground cardamom and icing sugar in a mixing bowl until it reaches the soft peak stage (the peaks fall over when you take out the whisk). Serve slices of tart with a dollop of cream and the blood orange syrup.