Mix flour, starch, 200 ml of milk, sugar, salt, yeast and only egg yolks into a bowl. Work all the ingredients by amalgamating them well; the compound must be homogeneous and not excessively liquid (if necessary, adjusted with other milk or flour). Ankle an anti-stick pan with butter and pour small doses of dough with a mixture, so you can get discs of dough of homogeneous diameter. Cook each pancake quickly, first on one side and then on the other. Continue until all the dough is finished. Stack 3 pancakes on each of the four dishes and make them to your liking.