Stir the sugar, flour, almonds, and cinnamon in a large bowl until combined.
Rub the butter cubes into the flour mixture until it resembles coarse, moist breadcrumbs.
Stir in the beaten egg until the dough forms, then knead lightly into a ball.
Press three quarters of the dough into the base and sides of a 24cm fluted tart tin.
Spread the raspberry jam evenly over the dough base.
Roll the remaining dough to 3mm thickness and cut into 1.5cm strips.
Create a lattice pattern with the strips over the jam and chill for 30 to 60 minutes.
Bake at 190°C for 30 minutes until the pastry is pale golden brown.
Cool the tart in the tin before transferring to a serving board.
Dust with icing sugar and cut into wedges to serve.