Make the honey dough

• Whisk the eggs with the sugar, then add the softened butter, honey and baking soda.
• Sift in the cocoa powder and gradually add the flour, mixing until a soft, non-sticky dough forms.
• Wrap the dough and let it rest in the fridge.

Bake the cake layers

• Divide the dough into several equal pieces and roll each one out thinly on a floured surface.
• Bake the layers on a baking tray at 180 °C until set and slightly firm.
• Let the layers cool completely, then trim them to the same size and keep the trimmings.

Cook the custard cream

• Whisk the eggs with the sugar and flour, then pour in the milk and add the vanilla.
• Cook over low heat, stirring constantly, until the cream thickens, then let it cool to room temperature.
• Beat the softened butter and whisk it into the cooled custard until smooth.

Assemble the cake

• Spread custard cream over each cake layer and stack them.
• Cover the top and sides with the remaining cream.
• Crush the trimmings and press them onto the sides and top, then refrigerate to set.

Make the chocolate glaze

• Melt the dark chocolate with the butter and milk over low heat, stirring until smooth.
• Stir in the powdered sugar and let the glaze cool slightly.
• Pour the glaze over the chilled cake and let it set before serving.