Cut brown bread into slices, crumble or grate roughly. Mix with 1 tablespoon cinnamon, sugar and lemon peel. Peel the apples, stick out the core. Cut apples into slices.
Sprinkle with lemon juice. Grease an ovenproof dish (about 22 cm long and 10 cm high). Alternate layers of brown bread mixture, apple rings, sultanas and sour cream. Distribute the fat in small flakes on top.
Close the tin tightly with aluminium foil and bake in the preheated oven (electric oven: 200 °C/ gas: level 3) for approx. 45 minutes. Dust with cinnamon and serve hot. Decorate as desired with lemon balm leaves.