In a small, microwave safe bowl melt 2 cups chocolate chips in 30 second increments, stirring in between each interval. This should take 60-90 seconds.
Once melted, spoon about 2 Tablespoons of chocolate into each half sphere. Use a pastry brush or the back of a spoon to spread the chocolate around the whole sphere. Make sure the edges are well coated so that they are not fragile. Let set in the fridge or freezer until hardened, about 10 minutes. Once set, gently remove from the molds.
Lay 6 half spheres on a plate, face down.
In a small microwave safe bowl, melt ¼ cup chocolate chips in 30 second increments, stirring in between. This should take 30-60 seconds. Once melted, spoon into a baggie or piping bag. Snip a small corner in the bag. Drizzle one half sphere with melted chocolate. Place several mini, multi colored chocolate chips on top of the drizzle before it hardens. Repeat until you've done all 6. Let set in the fridge or freezer for 3-5 minutes until hardened.
Lay the 6 remaining, plain half spheres face up on a plate. Spoon 1 Tablespoon of hot cocoa mix into each half sphere. Top with one piece of cosmic brownie and several mini marshmallows.
Warm a small, microwave safe plate in the microwave for 45-60 seconds. Lay decorated, empty half sphere on the plate for a couple seconds until it begins to melt the edges. This creates an even edge and a sort of glue. Connect with the corresponding, filled half sphere so that the edges meet. Repeat with the remaining 5 spheres until they are all completed. Serve and enjoy!
To Serve Hot Cocoa
Set a hot cocoa bomb in the bottom of a mug and pour 6 oz of hot milk or water over top until the shell has melted in, releasing the hot cocoa powder, cosmic brownie and mini marshmallows. Stir with a spoon until fully combined.
Storage: Hot cocoa bombs may be stored in a baggie or airtight container for up to 2 weeks.