Cut the nougat into cubes. Stir pudding powder and 100 ml milk until smooth. Heat the remaining milk. Melt the nougat while stirring. Bring the nougat milk to the boil. Stir in pudding powder, bring to the boil and simmer for about 1 minute.
Season to taste with sugar.
Let the pudding cool down a little. Fold in the pistachios, except some for decoration. Divide the nougat pudding into four dessert glasses and let them cool down.
Wash and quarter the apple or pear and remove the core. Cut the flesh into small cubes and sprinkle with lemon juice immediately.
Sprinkle nougat pudding with the apple cubes and the remaining pistachios. Decorate with mint leaves.