Mix yeast with 1 teaspoon sugar until the yeast is liquid. Warm the milk lukewarm. Mix 350 g flour, 50 g sugar and 1 pinch of salt. Add yeast milk and egg. Knead to a smooth dough with the dough hooks of the mixer. When the dough forms into a ball, knead for about 3 minutes. Cover and leave to rise in a warm place for about 1 hour.
Grease an ovenproof pan (28 cm Ø; alternatively form a ring on the baking tray with aluminium foil). Briefly knead the dough on a little flour and roll out to a rectangle (approx. 30 x 50 cm). Spread with nougat cream, leaving an approx. 2 cm wide rim all around. Spread with frozen cherries. Roll up from the long side. Cut the roll in half lengthwise, but do not cut through completely at one end. Carefully form both strands of dough into a cord first, then into a wreath. Put them in the pan and let them rise again for about 30 minutes.
Preheat oven (electric cooker: 200 °C/circulating air: 180 °C/gas: see manufacturer). Bake for about 30 minutes, covering with baking paper after about 20 minutes. Take out and let cool down. Dust with icing sugar as desired.