Melt the melted candy melts in a double boiler or in a microwave-safe bowl. Stir until smooth.
Pour melted candy melts into the inside of 12 silicone sphere molds (2-inch diameter). Refrigerate for 5 minutes until the caramel is set, then repeat this process to thicken the caramel spheres. Refrigerate for 5 minutes, then carefully remove the caramel from the molds.
To each of the 6 half caramel spheres, add the following: 1 tablespoon hot cocoa, 4 mini marshmallows, and 2 quarts of caramel.
Heat a skillet until hot, then remove from heat. To seal the hot cocoa bombs, place a half sphere in the hot skillet so that it melts slightly at the edge. Carefully pick up the half sphere with the slightly melted edge and place it on top of a sphere filled with hot cocoa, marshmallows and caramel. Run your finger around the outside to smooth it out. Repeat this process until you have 6 hot cocoa bombs.
To decorate the hot cocoa bombs, place them on a tray or a piece of wax paper.
Melt the white candy melts in a double boiler or in a microwave-safe bowl. Stir until smooth. Pour the melted white candy melts into a small resealable plastic bag and snip off a small corner. Gently squeeze the melted white candy over the top of the hot cocoa bombs in a decorative drizzle. If desired, top with sprinkles before the melted white candy sets.
To serve, add one hot cocoa bomb to a mug. Pour in 8 to 10 ounces of hot milk, stir and serve.
NOTES
As with any candy or chocolate, it is best to keep them in a cool, dark place, away from heat and direct sunlight. You can store them in the refrigerator if you are going to keep them for more than a few days.