Whisk the flour, 30 g powdered sugar and 1/4 tsp salt in a mixing bowl. Rub in the cold butter with your fingertips until the mixture looks like coarse sand with a few pea-sized pieces. Stir in the egg yolk and 1 tbsp cold water, adding a second spoonful only if the dough won't clump when squeezed. Press into a disk, wrap and chill for 30 minutes.

Roll the dough between two sheets of parchment to about 3 mm thick and 30 cm across. Lift it into the 23 cm / 9-inch tart tin, press it into the corners and up the fluted sides, trim the excess and prick the base with a fork. Freeze the lined tin for 15 minutes while the oven heats to 190 C / 375 F with the 33 x 46 cm baking sheet on the middle rack.

Line the shell with parchment, fill with pie weights and set the tin on the hot baking sheet. Bake for 15 minutes, lift out the parchment and weights, then bake 5 minutes more until the base looks pale gold and dry. Brush the hot shell with the beaten egg white to seal it, and lower the oven to 180 C / 350 F.

Beat the softened butter and granulated sugar with an electric hand mixer for 3 minutes until pale and fluffy. Beat in the eggs one at a time, then the almond extract and a pinch of salt. Fold in the ground almonds and 25 g flour until no streaks remain.

Spread the jam in a thin layer over the sealed base. Spoon the frangipane on top and smooth it to the edges. Press the raspberries into the surface with the points up, about halfway down, then scatter the flaked almonds over the top.

Bake on the baking sheet for 35 minutes, until the top is deep golden and puffed and the center springs back when pressed lightly. A skewer in the center should come out free of wet batter, though a smear of jam is fine.

Cool the tart in its tin on a wire rack for 30 minutes, then push it up from the removable base. Dust with 1 tbsp powdered sugar and serve warm or at room temperature.