The biscuit on kefir (buttermilk)

• 0,5 litres of kefir (buttermilk)
• sugar 200 gr
• ½ teaspoon of salt
• ½ teaspoon of soda
• Vanillin
• 2 eggs
• 1,5 – 2 cup of a flour
• softened margarine of 100 gr or butter

Separate the yolk and white. Mix the egg white with sugar. Separately mix the yolk well. Mix the yolk and white together. Add margarine or butter, kefir or buttermilk, First put soda in the kefir. Then add salt, vanilla and flour. Optional, in the dough raisin, nuts, it is possible apples, a cherry, and dried fruits. Put oil in a cake pan, put the dough. Bake 30 –40 minutes at the average temperature (350 F)