Preheat oven (electric cooker: 200 °C/circulating air: 180 °C/gas: see manufacturer) and preheat an ovenproof pan (24 cm Ø; with lid) in the oven. Whisk the egg, 60 g sugar, vanilla sugar and 1 pinch of salt until creamy. Add ricotta and flour and stir in. Grease the hot pan. Pour the dough into the pan and smooth it down. Bake in the closed pan on the lowest shelf in the hot oven for about 10 minutes.
Squeeze 1 tangerine and caramelise 2 tablespoons of sugar in a small pot. Deglaze with juice and simmer until the caramel is dissolved. Let cool down briefly.
Peel and slice the 2nd mandarin. Peel the grapefruit so that the white skin is completely removed. Use a sharp knife to cut the flesh out between the parting skins. Mix the fruit with the caramel.
Remove the pancake from the oven and let it cool down as desired. Remove the pistachios from their shells and chop them roughly. Arrange the citrus salad on the pancake. Sprinkle with pistachios.