Knead all ingredients except the water in a large bowl with the dough hook of the hand mixer and gradually add the water. Knead everything for about 5 minutes. Pour the dough into the mold, smooth it out and sprinkle with the remaining oat flakes.
Bake in the preheated oven for about 30 minutes on the middle rack. Then reduce the temperature to 200 ° C and bake for another 30 minutes. If necessary, cover with aluminum foil or baking paper if the bread becomes too dark.