Russian
Whisk the eggs with the sugar in a heatproof bowl, add the honey and butter, and set the bowl over simmering water, whisking, for 5 minutes until the butter melts.
Whisk in the baking soda and keep whisking for 2-3 minutes until the mixture foams and turns golden.
Take the bowl off the heat, mix in the flour to a soft dough, and divide it into 6 pieces; heat the oven to 180C.
Roll each piece thinly on baking paper, cut out a 20 cm round using a plate as a guide, keep the trimmings, and bake for 4-5 minutes until golden.
Bake the trimmings until dark golden, let them cool and crush them into fine crumbs.
Whisk the sour cream with the powdered sugar and spread it between the cooled layers and over the top and sides of the cake.
Cover the cake with the crumbs and refrigerate it overnight so the layers soften before cutting into 8 slices.