How to make
Mix the yoghurt with the baking soda and stir. Once it becomes effervescent, add it to the beaten eggs, sugar, salt and oil. Knead a soft dough, while adding flour.
Divide the dough up into 8 equal-sized parts, shape them into balls, roll them out into round sheets and bake in an oiled tray in a moderate oven until reddened.
For the cream, set aside 1 1/5 cups (300 ml) of the milk, to it add the beaten eggs with the sugar and vanilla, add the flour and stir until smooth.
Put the rest of the milk on low heat to come to a boil, then pour the creamy mixture into it in a thin trickle while stirring nonstop, until thickened.
Start assembling the cake by stacking the baked sheets on top of one another after smearing them generously with cream. Press down on each sheet lightly, to prevent hollow spaces from forming.
Leave the assembled cake to soften, trim the sides off evenly all around.
Smear with cream and sprinkle with ground walnuts.
