Combine the chocolate and butter in a medium bowl and melt either in microwave or over a pot of boiling water, stirring until smooth.
Add molasses, vanilla bean paste and brown sugar and whisk until thoroughly incorporated. Set aside to cool.
Combine the flour, cocoa powder, salt and baking soda in a large bowl and whisk together.
Beat the egg into the wet mixture and stir until combined.
Add the wet ingredients into the dry and stir until well combined.
Transfer the batter onto a piece of parchment paper and shape into a log about 2 inches wide. Roll parchment paper and twist sides to create a cylinder and place in refrigerator for 1-2 hours.
Preheat oven to 325 degrees.
Line two baking sheets with parchment paper, cut dough into rounds about 1/4-1/3 inch thick and place on baking sheets about 2-3 inches apart from each other.
Bake for 12-15 minutes, remove from oven and let cool on the baking sheet for 5 minutes before transferring to a cooling rack to cool completely.
For the strawberry marshmallow fluff
Place the freeze dried strawberries in a food processor and process until they become a powder-like consistency. Set aside.
Combine the gelatin and 1/4 cup of cold water in the bowl of a stand mixer fitted with the whisk attachment.
Combine the remaining 1/3 cup of water, sugar and vanilla in a small sauce pot over medium-high heat. Stirring occasionally, bring to a boil and cook until mixture reaches a temperature of 240 degrees Fahrenheit using a candy thermometer.
Once at temperature, turn the mixer to medium-low speed and slowly pour the sugar mixture into the bowl while mixing.
Increase mixer speed to medium-high and let mix until marshmallow texture begins to form.
Slowly add in the strawberry powder and continue to let mix until incorporated.
Spread fluff on bottom side of one of the cookies and top with another cookie to form a sandwich.