Melt 2 cups of the white chocolate chips in the microwave in 30 second bursts until smooth. Try to stir the chocolate as little as possible, as this is what can make it split!
Fill each cavity of a silicone mould until covered. You can do this with a spoon drawing chocolate up the sides but a silicone pastry brush might help. Allow to set.
Follow up with another layer of melted white chocolate around the top edge of each cavity where the two spheres are going to join. A thicker edge is better, but keep in mind that you don't want to fill the cavity too much with chocolate as it will run down the sides and pool at the bottom leaving less space for the filling. Again, allow to set.
To make the Fireball ganache, combine the remaining 2 cups of white chocolate, the heavy cream and the Fireball in a microwave safe bowl. Heat for one minute and stir well. If needed, heat again for an additional 30 seconds to make a smooth mixture. Allow to cool so you don't melt the chocolate shell filling the spheres!
Very gently, remove the sphere halves from the moulds. Using a warm frying pan (too hot and they'll melt too much!) gently melt the ridge of one sphere.
Fill one half full of the Fireball ganache. Each one should use about 2 tbsp of ganache.
Then take the other half of the shell and melt the edges in the frying pan.
Immediately place this shell on top of the filled half to make a complete sphere. Gently press along the sides where the two halves join to clean up the seal and remove any excess melted white chocolate. Set to the side as you finish building the remaining bombs.
To decorate, drizzle any remaining melted chocolate from making the spheres over the bombs and sprinkle with the sanding sugar.
To Make A Mug Of Hot Cocoa
Place one of these boozy hot cocoa bombs in the bottom of a mug.
Heat up 8-12 oz of milk or water in a saucepan or the microwave until it is just about to boil.
Slowly pour over the bomb and stir thoroughly. Enjoy!
Notes
You can keep these Hot Cocoa Bombs in an airtight container for up to 2 days on the countertop, or for roughly 2-3 weeks in the fridge. You can leave out the Fireball to make these more of a mocktail. Or use a different liqueur to change up the flavors.