Spray the individual Ramekins with non stick cooking spray or brush them with melted butter and sprinkles with cocoa powder to ensure cakes will come out of the ramekins 

Combine the chocolate and butter in a microwave safe bowl; microwave on high for 30 second increments until the chocolate and butter are melted and smooth; set aside 

In a mixing bowl with paddle attachment, combine the granulated sugar and corn starch and pour the melted chocolate into the mixing bowl and continue mixing on low speed until fully combined

Slowly add the eggs and egg yolks to the chocolate mixture and mix on medium speed until all eggs are incorporated

Pour the batter into a bowl or container and refrigerate for 30 minutes (the batter will thicken)

While the batter is chilling, preheat the oven to 350 degrees F and place the prepared ramekins on a baking sheet

Scoop the batter into ramekins and fill ¾ full

Bake for 20-22 minutes until the sides of the cake looks baked but the center still looks soft  

Remove the ramekins from the oven and allow them to cool for 2-3 minutes

Serve the cakes in the ramekins or gently place an inverted plate on the top of each ramekin and turn over (these will be hot so be careful)

Once the cake releases from the ramekins, garnish with fresh raspberries and mint and serve immediately!

If you would like to prepare these ahead of time, make the batter 2-3 days before your event and place in an air tight container in the refrigerator

When you are ready to use, allow the batter to come to room temperature, scoop the batter into ramekins on the day of your event and then bake 18-20 minutes before you are ready to serve!  

If you bake the batter when it is cold, it will require a longer baking time (approximately 25 minutes)