Bring milk to the boil in a pot. Add rice and let it swell at low heat for about 20 minutes. Finally stir in sugar. In the meantime, wash the apple and cut out the core.
Cut apple into sticks and sprinkle with lemon juice. Pour rice pudding into a small bowl. Add yoghurt and sprinkle with the drained apple pens. Serve decorated with mint leaves and apple slices as desired.