Put the apricots on a sieve and let them drain. Roughly dice the bread. Heat 25 g butter in a large frying pan and fry the bread cubes in it over a low heat, turning several times, for about 8 minutes until golden brown.
Mix 50 g sugar and cinnamon and sprinkle over the bread halfway through the toasting time. In the meantime whisk eggs, vanillin sugar, 100 g sugar, milk and cream. Place the toasted bread in a greased casserole dish, pour egg milk over it and spread apricots evenly on top.
Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 30 minutes. 10 minutes before the end of the baking time, spread 25 g butter in flakes over the casserole. In the meantime, roughly chop the pistachios.
Serve the casserole sprinkled with pistachios.