Melt the butter, then add the powdered sugar, salt, egg, and gradually mix in the flour. Mix well and form into a ball.

Chill the dough in the refrigerator for at least 1 hour.

Peel and cut the apples into large pieces. Sauté them with the butter and sugar until they are slightly caramelized. Set aside.

Line a tart pan with the shortcrust pastry, then spread the raspberries (slightly crushed) over the bottom.

Cover the raspberries with the apples.

Prepare the crumble topping by mixing the melted butter, flour, and sugar together, then sprinkle this mixture over the apples.

Bake for 30 minutes at 350°F (180°C). Serve warm or at room temperature.