Preheat and prep: Set your oven to 200°C (400°F) and place a baking tray on the middle rack to heat up. Generously butter the inside of four 150ml ramekins and dust them lightly with cocoa powder — tap out the excess. You’ll see a thin, even coating that will help the cakes release cleanly.

Melt the chocolate and butter: In a medium heatproof bowl, combine the chopped dark chocolate and melted butter. Microwave in 20-second bursts, stirring between each, until the mixture is smooth and glossy — about 60 to 80 seconds total. The chocolate should be fluid and shiny, with no lumps.

Whisk the eggs and sweetener: In a separate large bowl, whisk the eggs, granulated sweetener, and vanilla extract together until the mixture is pale, thick, and slightly foamy — this takes about 1 minute of vigorous whisking. You’ll see the colour lighten and the texture become airy.

Combine wet ingredients: Slowly pour the melted chocolate mixture into the egg mixture while whisking continuously. The batter will darken and become glossy, and you’ll smell the rich chocolate aroma. Whisk until fully combined and smooth.

Add dry ingredients: Sift the coconut flour, cocoa powder, and salt over the batter. Fold gently with a spatula until no streaks of flour remain. The batter will be thick but not stiff — it should drop slowly from the spatula. If using coffee, stir it in now.

Fill the ramekins: Divide the batter evenly among the four prepared ramekins, filling each about three-quarters full. Smooth the tops with the back of a spoon. At this point, you can cover and refrigerate them for up to 24 hours if making ahead.

Bake: Place the ramekins on the preheated baking tray in the oven. Bake for exactly 10-12 minutes. The edges should look set and slightly puffed, while the centre will jiggle when you gently shake the tray. The tops will be matte, not shiny, and a skewer inserted 1cm from the edge should come out clean.

Rest and serve: Remove from the oven and let the ramekins rest on a wire rack for exactly 1 minute. Run a thin knife around the edge of each ramekin, place a small plate on top, and invert. Lift the ramekin gently — the cake should release with a soft, molten centre spilling out. Serve immediately.