Ingredients
Method
- Preheat oven to 170°C / 150°C fan / Gas 3. Grease and line two 20cm tins.
- Melt chocolate and butter together over a pan of simmering water.
- Whisk sugar and eggs until pale, 2–3 minutes.
- Whisk in melted chocolate, then buttermilk and vanilla.
- Sift in flour, cocoa, bicarbonate of soda and salt. Fold gently.
- Divide between tins, bake 30–35 minutes.
- Cool in tins 10 minutes, then on a wire rack.
- Heat cream, pour over chocolate, stir smooth, add butter. Cool 20–30 minutes.
- Sandwich sponges with ganache, cover top and sides with remainder.
Notes
A few moist crumbs on the skewer is the sign to take the cake out — don't wait for a completely clean one.
Use good dark chocolate throughout, as it carries most of the flavour.
Un-iced sponges freeze well for up to 3 months.
Bring to room temperature before serving for the best texture and flavour.