Prepare the ramekins by greasing well with the extra butter.

Line the base of each ramekin with baking paper cut into a small circle.

Place a small amount of cocoa powder into the base of each ramekin and shake it around until the sides are completely covered (the powder will stick to the butter).

Shake off any excess cocoa powder and set aside.

Place the chocolate and butter into a microwave safe bowl and heat for 3-4 minutes on 50% power, stirring every 30 seconds until just melted and completely smooth.

Set aside to cool to room temperature.

Meanwhile, whisk the eggs, additional egg yolks and caster sugar in a bowl until pale and smooth.

Add ¼ of the egg mixture to the cooled chocolate mixture and beat until smooth.

Repeat until all of the egg mixture has been completely incorporated and the mixture is smooth.

Gently fold through the flour.

Divide the mixture evenly between the prepared ramekins and place into the fridge for at least 30 minutes (up to 24 hours).

Preheat oven to 180 degrees celsius.

Place the ramekins onto a baking tray and place into the oven.

Cook for 10-12 minutes or until a slight crust has formed and cakes are beginning to come away from the sides.

Remove from the oven and set aside for 2 minutes.

Gently loosen the chocolate cakes from the sides and then place a plate on top of the ramekin and gently flip it over.

If you think the chocolate lava cake is not going to come out, gently run a butter knife around the edge of the ramekin before turning out (if the ramekins are well greased and covered in cocoa powder - they should be absolutely fine!).

Remove the baking paper circle and serve with fresh berries or ice-cream immediately.