Wash, clean and quarter the strawberries and mix with 1 tbsp. flour. Mix 250 g flour, ground almonds and baking powder. Cream butter, 200 g sugar and vanilla sugar with the whisk of the hand mixer.
Stir in eggs, milk and sour cream one after the other. Stir in flour mixture.
Put half of the dough into a greased, floured box form (approx. 30 cm long, 1 3/4 litres capacity). Stir the strawberries, except for 2 tbsp., into the rest of the dough, also into the tin and smooth it down.
Spread the rest of the strawberries on top. Mix 30 g sugar and flaked almonds and sprinkle over the dough. Bake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for 1-1 1/4 hours.
If necessary, cover with foil about 10 minutes before the end of the baking time.
Remove the cake, let it cool down in the mould for about 30 minutes, then tap it carefully out of the mould at an angle (otherwise the crust will fall off) and let it cool down on a cake rack. Whipped cream is delicious with it.