Heat 150 ml drinking water to 36-38 °C, add yeast and stir until smooth. Pour in 130 g flour, carefully knead and put in a warm place for 30 minutes to rise. Meanwhile, melt and cool the butter. Beat eggs with salt, and whip yolks with brown and vanilla sugar into fluffy foam. Mix cream, butter and egg mass. Sift the flour heaped on a cooking surface, make a groove in the center, and pour in the liquid yeast and the creamy mixture. Knead dough, and knead it out until fully elastic: it should not be sticky. Put the dough in a clean bowl, cover and leave in a warm place for 2 hours to rise. Meanwhile, the dough should be kneaded twice. Preheat the oven to 180 °C. Place the dough in the kulich tins so that it occupies no more than half the volume in each tin. Allow to rise for 20-30 minutes. Bake until done: kuliches should rise highly. If stick a wooden skewer into the cooked kulich, it must come off clear. Cool kuliches, laying them on one side on a cushion covered with a towel. Decorate to your liking.