Prepare the Ramekins: Preheat your oven to 200°C (180°C Fan). Generously grease four 175ml ramekins with butter, making sure to cover the entire inside surface. Dust the inside with a little plain flour or cocoa powder, tapping out any excess. Place the prepared ramekins on a baking tray.

Melt the Chocolate and Butter: Place the chopped dark chocolate and butter in a heatproof bowl set over a saucepan of gently simmering water (a bain-marie). Make sure the bottom of the bowl doesn't touch the water. Stir occasionally until completely melted and smooth. Remove from the heat and set aside to cool slightly.

Whip the Eggs and Sugar: In a separate large bowl, using an electric hand mixer or a stand mixer with the whisk attachment, beat the whole eggs, egg yolks, caster sugar, and vanilla extract together on high speed. Continue for about 5-7 minutes, or until the mixture is pale, thick, and has doubled in volume. When you lift the whisk, it should leave a ribbon-like trail on the surface for a few seconds.

Combine Wet Ingredients: Gently pour the slightly cooled chocolate-butter mixture into the whipped egg mixture. Using a spatula, carefully fold them together until just combined. Try to be as gentle as possible to avoid knocking out all the air you've just whipped in.

Fold in Dry Ingredients: Sift the plain flour and salt over the chocolate-egg mixture. Fold in gently with your spatula until no streaks of flour remain. Again, avoid overmixing.

Fill the Ramekins: Divide half of the batter evenly among the four prepared ramekins. Spoon one teaspoon of cherry conserve into the centre of each one. Top with the remaining batter, ensuring the jam is completely covered. What works best for me is tapping each ramekin gently on the worktop to level the batter.

Bake to Perfection: Place the baking tray in the preheated oven and bake for 12-14 minutes. The edges of the cakes should look set and slightly pulled away from the sides, but the very centre should still have a distinct wobble when you gently shake the tray. This is the secret to the 'lava'.

Rest and Serve: Carefully remove the baking tray from the oven. Let the cakes rest in their ramekins for just 1-2 minutes. This is a crucial step! Then, place a serving plate on top of a ramekin and, using oven gloves, confidently flip it over. Lift the ramekin away. The cake should slide out easily. Dust with icing sugar or cocoa powder and serve immediately.