Knead the flour, sugar, egg and butter in small pieces first with the dough hooks of the hand mixer, then with your hands to a smooth dough. Cover and chill for about 30 minutes. Wash, halve and stone the apricots.
Stir the jam until smooth. Grease a square tart tin (approx. 22 x 22 cm). Roll out the dough squarely (approx. 25 x 25 cm) on a work surface dusted with flour. Line the tin with the dough, cut off any protruding edges.
Put half of the jam on the bottom and spread it. Spread the apricots with the cut surface facing upwards. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) on the bottom shelf for approx. 30 minutes.
After 10 minutes, spread the remaining jam on the apricots. Sprinkle the flaked almonds on the tart 5 minutes before the end of the baking time and finish baking. Let it cool down on a cake rack. Dust the tarte with icing sugar and decorate with lavender flowers.
Whipped cream is delicious with it.