In a mixing bowl mix eggs, flour, 1 cup of kefir, baking soda, sugar, salt and oil with a whisk. When the mixture is smooth and has no lumps add remaining kefir and water. The consistency should be the same as of heavy cream.

Let stand for 20-30 minutes. You should see small bubbles on the surface of your batter. Preheat your non-stick frying pan on medium heat and grease it with an odourless oil. ( I usually put some oil on a paper towel and rub the frying pan with it to ensure even coating, I re-apply oil before frying each crepe.)

With a ladle or a measuring cup pour ¾ cup of batter in the pan and tilt the pan slightly so batter runs to the edges forming a thin and round crepe. Cook it until batter looks dry, then flip with a spatula and cook for 2-3 more minutes. Remove to a platter.

Repeat with the next crepe and continue cooking until the batter is used. Stack the blini on top of each other.

This recipe make 10 23 cm crepes. If you want a tall cake double the recipe.

In a saucepan combine rhubarb, sugar and water, turn the heat on and heat very gently until sugar melts, cover with a lid and let it simmer for 5 minutes until rhubarb it tender but not falling apart.

Turn the pot over a fine sieve set over a bowl. Save a few pieces of rhubarb to decorate the top of the cake and set them aside.

Mix custard powder and sugar in a saucepan, add 4 tbsp of milk and mix the ingredients to form a smooth paste.

Split the vanilla bean in half lengthwise and scrape the seeds out with the blade of a knife.