Step 1

Start by making the pastry. Sift the flour, icing sugar and a pinch of fine salt into a large bowl. Tip in the butter and, using your fingertips, rub it into the flour and sugar until it resembles breadcrumbs. Add the egg yolk and 2 tsp cold water, using a table knife to mix together, then use your hands to bring together into a dough. Knead briefly until smooth. Shape into a flat disc, wrap in a food bag or baking parchment and chill for 20 minutes.

Step 2

Tip the pastry onto a lightly floured work surface and roll out to 0.3cm thick. Use to line a 23cm deep, loose-bottomed fluted tart tin, leaving the excess pastry to overhang. Prick the pastry all over with a fork, then chill for 30 minutes. Preheat the oven to 200°C, gas mark 6 and put a baking tray in to heat up.

Step 3

Scrunch a sheet of baking parchment, then open it out and use to line the chilled pastry case. Fill with ceramic baking beans or rice. Put on the preheated tray and bake for 15 minutes, then remove the beans/rice and parchment and bake for a further 5 minutes until pale golden. Remove from the oven and reduce the temperature to 180°C, gas mark 4. Trim off any overhanging pastry with a serrated knife.

Step 4

While the pastry is baking, make the filling: in a large bowl, use an electric hand mixer to beat together the butter and sugar until pale and fluffy (about 5 minutes). Beat in the eggs, one at a time, until well combined, then fold in the ground almonds, a pinch of salt and the almond extract, if using.

Step 5

Spread the jam evenly over the pastry base, then spoon over the filling, working from the outside in. Carefully level it out with a palette knife or the back of a spoon. Scatter over the almonds and bake for 35-40 minutes until golden, well risen and just set in the centre. Leave to cool in the tin for 5 minutes, then transfer to a wire rack to cool completely.

Step 6

To decorate, sift the icing sugar into a small bowl and stir in 1-2 tsp water until it reaches a drizzling consistency. Drizzle over the tart, then serve with double cream, if liked.