For sourdough crumble fresh yeast, pour in warm milk (0.5 cups), add 1 tsp sugar and a little flour. Cover the container with a sponge and wait until the foam cap appears. In a large bowl, mix the sourdough, the remaining milk, preheating it, eggs and flour. Knead the dough, cover the bowl with a napkin and put it in a warm place for proofing. It will take about 1 hour. Do not forget to stir the dough from time to time so that it does not run away. Add vegetable oil to the dough, which will significantly improve the taste of pancakes and you will not need to lubricate the pan when frying.