Step 1

Preheat the oven to 170C/325F/Gas Grease a 23cm/9in springform cake tin with a little oil and line the base with baking parchment.

Step 2

Measure and sift the cocoa powder into a bowl or jug and whisk in the boiling water until you have a smooth, chocolatey, still runny (but only just) paste. Whisk in the vanilla extract, then set aside to cool a little.

Step 3

In another smallish bowl, combine the ground almonds (or flour) with the bicarbonate of soda and a pinch of salt.

Step 4

Put the sugar, olive oil and eggs into the bowl of a freestanding mixer with the paddle attachment (or other bowl and whisk arrangement of your choice) and beat together vigorously for about three minutes until you have a pale-primrose, aerated and thickened cream.

Step 5

Turn the speed down a little and pour in the cocoa mixture, beating as you go, and when all is scraped in you can slowly tip in the ground almonds (or flour) mixture.

Step 6

Scrape down and stir a little with a spatula, then pour this dark, liquid batter into the prepared tin. Bake for 40-45 minutes or until the sides are set and the very centre, on top, still looks slightly damp. A cake tester should come up mainly clean but with a few sticky chocolate crumbs clinging to it.

Step 7

Let it cool for 10 minutes on a wire rack, still in its tin, and then ease the sides of the cake with a small metal spatula and spring it out of the tin. Leave to cool completely or eat while still warm with some ice cream, as a pudding.