Medovik

Set a heatproof bowl over a pan of simmering water and add the honey, caster sugar and the 100g of butter for the layers.

Stir for 4-5 minutes, until melted and smooth.

Take the bowl off the heat and whisk in the bicarbonate of soda.

The mixture will foam up to two or three times its volume and turn a shade darker within seconds. That reaction is the leavening and much of the colour; if nothing happens, the soda is stale and the layers will bake hard.

Let the foam settle and cool to about 60C/140F, warm rather than hot to a fingertip.

Whisk in the beaten eggs in a thin stream. Added to a hotter mixture they scramble into threads that never disappear.

Stir in the salt, then the flour in three additions, to a soft sticky dough.

Wrap and chill for 1 hour, until firm enough to handle.

Heat the oven to 180C/350F and line two baking trays.

Divide the dough into 8 pieces of about 110g, keeping the ones you are not using in the fridge.

Roll each piece between two sheets of baking parchment to a rough circle 2mm thick, dusting with a little extra flour if it sticks.

Bake each layer on its parchment for 4-6 minutes, until deep gold and dry to the touch. They colour at the edge first and go from done to burnt quickly.

Cut each layer to a 20cm circle the moment it leaves the oven, using a plate as a guide.

Do this within about 30 seconds. The layers crisp as they cool and a cold one shatters instead of cutting.

Keep every trimming.

Cool the discs flat on a rack. They will be hard and snap cleanly, which is correct at this stage.

Crush the trimmings to fine crumbs with a rolling pin or in a processor.

Whip the cold double cream to soft peaks.

Fold in the soured cream, icing sugar and vanilla, until smooth and thick enough to hold a line drawn through it.

Do not whisk once the soured cream is in. Its structure breaks under the beater and the filling turns to liquid.

Use soured cream of at least 20% fat. Anything thinner never sets, soaks the layers unevenly and runs out of the sides of the finished cake.

Stack the cake on a serving plate: a layer, about 120g of filling spread right to the edge, then the next layer, finishing with filling on top.

Press each layer down gently as it goes on so there are no air gaps.

Coat the top and sides with the crumbs, pressing them on with a cupped hand.

Refrigerate for at least 8 hours, and 24 if you can.

This wait is the recipe rather than a resting step. The layers go in as biscuits and come out as cake, because moisture from the filling moves into them and softens them through. Cut after 2 hours and you get a dry stack with cream between the sheets.

Cut with a long thin knife, wiping the blade between slices.