Mix flour and sugar in a bowl. Add vanilla and butter in pieces. First use the dough hooks of the hand mixer, then work into crumbles with your hands. Grease a square springform pan (24 x 24 cm). Put just under 3/4 of the crumbles into the form and press them to a smooth base
Stir the red fruit jelly until smooth, place on the base and spread, leaving a rim of approx. 5 mm free. Spread the rest of the crumble on top. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) on the 2nd rack for 40-45 minutes. Cool down on a cake rack, loosen the crust with a knife after about 10 minutes. Leave to cool in the mould. Remove from the tin, cut in half, cut the halves into approx. 10 strips each. Delicious with vanilla sauce
waiting time approx. 2 hours