Peel, halve and core apples. 1⁄2 Set the apple aside for the garnish, cut the rest into pieces. Bring to the boil with 2-3 tbsp. sugar, apple and lemon juice. Cover and cook over low heat for about 5 minutes.
Stir the starch and 2-3 tablespoons of water until smooth and bind the apples with it. Season with a little cinnamon and let it cool down.
Crumble the pumpernickel. Heat butter in a pan. Roast bread in it for about 2 minutes until crispy. Add 2 tablespoons sugar, another approx.
Roast for two minutes. Take out and let cool off.
Mix yoghurt, 2 tablespoons sugar and vanilla sugar. Whip the cream until stiff and carefully fold into the yoghurt. Layer pumpernickel, apple compote and yoghurt-vanilla cream in four glasses. Cut the remaining apple into fine slices and decorate the dessert with them.