Warm 4 tablespoons of milk lukewarm. Crumble yeast into it and dissolve. Sift 500 g flour into a bowl and press a depression in the middle. Add yeast milk and 2 tbsp. sugar, mix with some flour to the pre-dough.
Cover and leave to rise in a warm place for about 30 minutes.
Add the eggs, 1 pinch of salt and 2 tablespoons of sugar to the pre-dough and work into a smooth dough with the dough hooks of the hand mixer. Knead butter into flakes. Cover and leave to rise for about 1 hour.
Line 2 trays with baking paper. Knead yeast dough on a little flour. Divide into 16 equally sized pieces and form each into a roll of about 30 cm. Weave this into a braid (see picture).
Put them on the trays. Cover and leave to rise for about 20 minutes.
Whisk the egg yolk and 2 tablespoons of milk. Brush braids with it. Bake in a hot oven (electric oven: 200 °C/circulating air: 175 °C/gas: level 3) for 18-20 minutes one after the other.
Warm up the jam, stir until smooth. Brush the braids with the jam 5 minutes before the end of the baking time. Sprinkle with pistachios. Serve hot or cold.