Mix flour, cocoa powder, sugar, vanilla sugar, soda in a bowl.
In a separate container, add vegetable oil and soy sauce to the whey, mix.
In two or three doses, pour the liquid ingredients into the dry mixture. Whisk until smooth.
Pour the dough into a cupcake pan greased with vegetable oil. Put it in the oven, preheated to 180 degrees, for 35-40 minutes.
Here’s a cupcake turned out. Allow the cake to cool completely.
For the glaze, mix softened butter at room temperature, half the norm of powdered sugar and lemon juice. Whisk until fluffy, gradually adding powdered sugar.
Powdered sugar may need more or less.
Put icing on a completely cooled cupcake.