Dissolve yeast in 800 ml of lukewarm water. Add the baking mixture and knead to a soft dough with the dough hooks of the hand mixer. Cover and leave to rise in a warm place for about 45 minutes.
Knead again for about 1 minute. Add the hazelnuts. Fill into a greased box form (30 cm long) with a wet tablespoon and smooth it down. Cut the surface lengthwise with a knife.
Dust with flour and bake in a preheated oven (electric: 225 ° C/ gas: level 4) for 15 minutes. Then reduce the temperature (electric oven: 200 °C/ gas: stage 3) and continue baking for approx. 1 hour.
Leave the bread to cool slightly in the mould. Turn out of the mould and let it cool down completely. Results in approx. 30 slices.