01 - Place the semi-sweet or dark chocolate in a heatproof bowl over simmering water and stir until fully melted and smooth.
02 - Spoon approximately 1 tablespoon of melted chocolate into each silicone sphere mold cavity (2.5–2.75 inches diameter). Use a brush or spoon to evenly coat the sides. Chill in the refrigerator for 10 minutes.
03 - Repeat the coating process to reinforce the shells and chill again for 10 minutes until set.
04 - Carefully remove the hardened chocolate shells from the molds.
05 - Place 1 tablespoon hot cocoa mix, mini marshmallows, and crushed peppermint candies into half of the shells.
06 - Warm a plate slightly. Press the edge of an empty shell onto the plate to soften, then immediately place it over the filled shell and press gently to seal. Repeat for all cocoa bombs.
07 - Drizzle melted white chocolate and sprinkle extra crushed peppermint candies over the sealed bombs. Allow to set.
08 - Place a cocoa bomb in a mug, pour 1 cup (250 ml) hot milk over it, stir well, and enjoy.