Put the flour in a bowl and press a depression in the middle. Heat 100 ml milk. Crumble yeast into the hollow, add 1 tbsp. sugar and milk, mix with some flour from the rim to a thick paste. Cover and leave to rise in a warm place for about 15 minutes. Wash the orange thoroughly, dab dry and rub the peel thinly.
Squeeze the juice from one half. Coarsely chop the walnut kernels. Melt butter in a pot, add 100 ml milk. Add 140 g sugar, lukewarm fat-milk mixture, egg, orange peel and 2-3 tbsp. orange juice to the pre-dough. Knead everything to a smooth dough with the dough hooks of the hand mixer. Knead in walnuts. Cover and leave to rise in a warm place for about 45 minutes. Knead the dough on a floured work surface and roll out to a round flat cake (approx. 32 cm Ø). Place on a baking tray lined with baking paper and leave to rise for a further 30 minutes. In the meantime, wash the grapes, drain and pluck. Press the grapes into the dough, sprinkle with pine nuts and 1 tbsp.
Cover and leave to rise in a warm place for about 45 minutes. Knead the dough on a floured work surface and roll out to a round flat cake (approx. 32 cm Ø). Place on a baking tray lined with baking paper and leave to rise for a further 30 minutes. In the meantime, wash the grapes, drain and pluck. Press the grapes into the dough, sprinkle with pine nuts and 1 tbsp. sugar. In the preheated oven, 2nd rail from below, (electric cooker: 200 °C/ circulating air: 175 °C/ gas: level 3) for about 25 minutes. Tastes best lukewarm
1 hour waiting time