In a saucepan over medium-high heat, bring the cream to a boil. Pour over the chocolate and let sit 2 minutes. Whisk in the butter until the mixture is smooth. Place the bowl over an ice-water bath until the mixture cools and is spreadable.
Using a pastry bag fitted with a plain tip, pipe about 5 ml (1 teaspoon) ganache onto the bottom of each cookie. Place three raspberries side by side on half the cookies and top with the remaining cookie, like sandwiches.