Preheat the oven to 175°C. Sift together all the dry ingredients except the sugar.

Grease a springform pan and line it with parchment paper.

Beat the butter and sugar until pale and creamy. Add the eggs one at a time, beating for about a minute after each addition, until fully combined.

Fold in the dry ingredients on low speed until just mixed, then add the milk and mix on low until smooth. The batter is fairly thick, not runny at all.

Pour into the pan, smooth the top, and bake for 30-40 minutes — start checking after 35 minutes, since it may finish early. Don't leave it in too long, since chocolate cake burns quickly, and this cake shouldn't be too firm. Once baked, let it rest 5 minutes before removing from the pan to cool.

For the cream: melt the chocolate in a double boiler or microwave for 2-3 minutes, then let it cool. Whip the cream with the powdered sugar, adding the melted chocolate as you whip. Once the cream holds its shape, refrigerate for about half an hour until firm.

Once the cake is fully cooled, trim about a centimeter off the domed top and edges, then slice into two or three layers with a sharp knife depending on your pan size; pulse the trimmings into crumbs in a food processor.

Moisten each cake layer with a little milk, spread with cream, and repeat for each layer, finishing with cream around the sides too. Cover the sides with the cake crumbs, and dust the top with cocoa powder and decorate with more cream.

After this step, the cake goes into the fridge to rest for 8-9 hours so the cake, cream, and chocolate meld together completely.