For the base, knead all the ingredients in a bowl. Then shape into a ball, wrap in plastic wrap and let rest in the refrigerator for about 1 hour. Then press into a greased and lined with baking paper mold and put in the cold again for 15 minutes.
Mix sugar, salt and flour for the topping. Beat the eggs and egg yolks, add the flour mixture and briefly stir in the butter and buttermilk. Carefully pour the mass on the prepared soil.
Bake at 175 ° top / bottom heat for about 40 minutes until golden brown. It is advisable to turn the cake 180 ° while it is baking so that it bakes evenly on all sides.