Preheat your oven to 425° F. Spray the ramekins with non-stick cooking spray, give them a dusting of cocoa powder, and place them on a baking sheet. Set aside.
In a large microwave-safe bowl, add the butter, and bittersweet and semisweet chocolate. Place the bowl in the microwave and cook on high for about a minute, until the butter is melted. Stir to combine until everything is blended together.
Stir in the confectioners sugar and continue to stir until well blended.
Add the eggs and egg yolks and continue to stir followed by the vanilla extract. Stir until incorporated into the batter.
Add the flour and kosher salt and continue to stir.
Divide the mixture among the four ramekins. Take a chocolate truffle and place it in the center of the lava cake batter in one of the ramekins, and press down. Using a spoon, cover the truffle with the batter. Repeat the process until all the truffles have been placed and covered.
Place the ramekins in the oven and bake for 12-14 minutes or until the sides appear solid and firm. Remove the ramekins from the oven and allow to cool for about a minute. Cover each ramekin with an inverted plate and turn over.
Garnish with additional raspberries, mint, and/or strawberries and serve.