TOTAL Time: 40 Min
Chop the dark chocolate bars into fine pieces and place them in a large microwave-safe bowl. To properly temper chocolate, microwave the chocolate in 10-second intervals, giving a stir in between. After each heating interval, check the temperature of the chocolate with an instant-read thermometer. The temperature needs to be between 88-90 °F. If it goes above 90 degrees, the chocolate will change into a dusty matte brown color once set, which you want to avoid.
Once the chocolate is melted and reaches between 88-90 degrees Fahrenheit, pour the melted chocolate into the silicone molds and evenly distribute a thick layer of chocolate with a small spatula or pastry brush. Now place the chocolate filled molds into the fridge and chill for 10-15 minutes.Wearing food-grade gloves, remove the chocolate from the mold.
Heat a nonstick pan over medium-low heat, then slightly melt the rim of half of a chocolate spheres in the hot pan. Place them open side up and fill them with hot cocoa mix and a few mini marshmallows. Then melt the rim of the remaining half and seal the hot cocoa bombs with another warmed half sphere.