Prepare the oven and tins – Preheat the oven to 180°C (350°F) and grease two 8-inch cake tins. Line them with baking parchment.

Combine dry ingredients – In a bowl, sift together self-raising flour, cocoa powder, and malted milk powder to remove lumps.

Cream butter and sugar – Beat the butter and caster sugar until pale and fluffy. This step adds air to the batter.

Add eggs gradually – Mix in the eggs one at a time, beating well after each addition.

Fold in dry ingredients – Gently fold the flour mixture into the batter. Add milk to loosen the consistency.

Divide and bake – Pour the batter evenly into the prepared tins and bake for 20–25 minutes until the sponge springs back when touched.

Cool completely – Leave the cakes in the tins for a few minutes, then transfer them to a cooling rack.

Prepare the frosting – Melt the dark chocolate and let it cool slightly. Beat butter and icing sugar, then mix in the chocolate, malt powder, and milk.

Assemble the cake – Spread frosting over one cake layer, place the second layer on top, and frost the surface evenly.