For the pastry, pulse 250g of all-purpose flour, ¼ teaspoon of fine sea salt, 2 tablespoons of icing sugar, and 140g of cold cubed butter in a food processor to fine crumbs.
Beat 2 egg yolks with 4 tablespoons of cold water, add to the crumbs, and pulse until the dough comes together. Wrap and chill for 30 minutes.
Preheat the oven to 400°F / 200°C. Roll out the pastry to a 10in / 25cm circle and line an 8in / 20cm fluted tart pan.
Line the pastry with parchment paper and baking beans and bake for 15 minutes. Remove the paper and beans and bake for 7-10 minutes more.
For the filling, beat 100g of softened salted butter with 100g of superfine sugar. Beat in 50g of ground almonds, 1 teaspoon of almond extract, and 2 beaten medium eggs.
Spread 3 tablespoons of raspberry jam over the pastry, spread the filling on top, and scatter with 50g of sliced almonds. Bake for 25-30 minutes, until golden and firm, then cool in the pan.
Mix 80g of icing sugar with 1 teaspoon of water, adding a few more drops if it is too thick, and drizzle over the cooled tart.
