Place the peanut butter candy melts in a microwave-safe bowl and melt in the microwave per the directions on the package. I start in 30 second increments to make sure I do not over cook the candy melts.
Place 1 tablespoon melted candy melt into one half of a bomb mold and, using the bottom of your tablespoon measuring spoon, press the chocolate up the sides of the mold, keeping it thick but even.
Repeat with 12 half sphere molds. Reserve the remaining melted candy melts.
Place the chocolate-filled bomb molds into the freezer for 5 minutes.
Remove the molds from the freezer and gently peel the silicone away from the chocolate cups.
Smooth the edges if needed.
Fill 6 of the molds with 2 tablespoons of hot cocoa mix and 5 mini marshmallows.
Heat a plate or a flat-bottom bowl in the microwave until the surface of the plate is warm to the touch. Press one of the empty chocolate bomb halves open-side-down onto the flat portion of the warm plate for about 10 seconds. This will gently melt the rim of the chocolate cup.
Immediately press this warmed-edge chocolate cup to the top of one of the filled cups. This will join the two halves of the hot cocoa bomb.
With the reserved melted peanut butter candy melts, pipe a little bit on top of each hot cocoa bomb and immediately place a teaspoon of the gold sprinkle pearls on top of the melted chocolate.
Place the hot cocoa bombs into the freezer for 5 minutes to get them to set, then remove and store in an airtight container until you’re ready to use.