Blueberry custard tart
This Scandinavian-style tart is made with rye pastry and sour cream.
Serves 10-12
Preparation time: 30 minutes, plus cooling and chilling Cooking time: about 90 minutes
For the pastry
100g plain flour, plus extra to dust 125g wholemeal rye flour 175g unsalted butter, chilled 50g caster sugar
1 large egg, separated
For the filling
600ml double cream
300ml sour cream
9 large egg yolks
100g caster sugar
1tsp vanilla extract
125g blueberries
Icing sugar, to dust (optional) 1 Make the pastry: in a large bowl, mix together the flours. Cube the butter, then rub it into the flour with your fingertips until it resembles breadcrumbs. Mix in the sugar, then the egg yolk and 11/2tbsp cold water until the pastry comes together. Knead briefly until smooth. To make pastry in a food processor: pulse cubed butter and flours until mixture resembles breadcrumbs. Pulse in sugar. Mix yolk and 11/2tbsp cold water; add to processor and pulse until pastry clumps together. Remove from processor bowl; knead briefly.
2 On a floured surface, roll out pastry to line a 4cm deep, 23cm round fluted tin (wrap and reserve any spare pastry at room temperature). Chill the lined tin for 30min.
3 Preheat oven to 190°C (170°C fan) mark 5. Line the pastry with baking parchment and fill with baking beans. Put on a baking sheet and blind bake for 18-20min until the pastry sides are set. Carefully remove the parchment and beans. Patch up any areas with reserved pastry if necessary. Brush the pastry with egg white and return to the oven for 2min until firm and glossy.
4 Lower the oven temperature to 140°C (120°C fan) mark 1. In a small pan, mix the creams together and bring to the boil. Meanwhile, in a heatproof bowl, mix together the 9 egg yolks and sugar. Gradually pour in the hot cream mixture, whisking all the time. Strain through a sieve into a jug and stir in the vanilla.
5 Carefully pour the custard into the pastry case (still in the tin). Lightly scatter over the blueberries (so they float). Bake in the oven for 1hr 5min-1hr 10min until the custard is just set but has a slight wobble if the tin is tapped. Cool in the tin on a wire rack.
6 Transfer to a serving plate, dust with icing sugar and serve at room temperature.