First, Place a plate in the freezer

Melt chocolate in a microwaveable bowl on high for 60 seconds.
Stick a spoon in the chocolate to see if it's beginning to melt. If it is you will need to decrease the power percentage on your microwave down to 60 percent and continue.

Continue to warm up chocolate in 30 second intervals stirring between each time.
This may take 2-4 times.

When you stir the chocolate and see it's mostly melted, heat for 15 seconds and stir until all lumps are gone and the chocolate is smooth.

Use a spoon to drop a dollop into the first cavity of the silicon mold.

Use the back of the spoon to coat the mold completely.

Wipe away any excess chocolate.

Freeze for 10-15 mins.

Prepare your set up for the contents inside of the cocoa bombs.

Remove plate and mold from the freezer.

Carefully remove each half heart from the mold and set them on the now cold plate (this keeps them from melting)

Spoon in 2 spoonfuls of cocoa mix (not an entire packet).

Add your surprise (marshmallows, sprinkles, or candies)

Connect the two ends of the heart together by either melting chocolate to serve as a glue (piping bag method) or place the top heart onto a heated plate to lightly melt the edges and stick together.