Bring 300 ml water, lemon juice and 3 tablespoons honey to the boil in a small pot. Wash apples, grate dry, cut in half and remove core generously with a ball cutter. Steam apple halves in the stock at low heat for about 6 minutes, turning once.
In the meantime, roughly chop the pistachios. Remove the apples. Heat butter and 1 tablespoon honey in a pan. Fry the apple halves for 2-3 minutes with the cut surface facing downwards, remove. Arrange apples on a plate, fill with caramel ice cream and sprinkle with pistachios.
Serve immediately.