Make the sponge cake dough. Break the eggs into a deep container and beat them well with a mixer. Add boiling water and continue mixing. Pour in the sugar. Beat until the egg mass doubles in size. Add flour, starch and baking powder. Mix carefully. Line a baking sheet with baking paper and spread the dough over the surface. Place in the oven, preheated to 180℃, for 10 minutes. Roll the still hot sponge cake into a roll and leave to cool.
Prepare the filling. In a bowl, beat the cream until soft peaks form. Add the powdered sugar and continue beating. Add the cream cheese and mix until smooth.
Make the glaze. In a heavy-bottomed saucepan, combine the sour cream, cocoa, sugar, and butter. Place over medium heat. Stir occasionally until the glaze is smooth. Remove from heat and let cool.
Assemble the roll. Unroll the dough. Grease its surface well with cream cheese cream, roll into a tight sausage. Pour the glaze over the roll. Refrigerate for 120 minutes.