Melt chocolate till smooth.
Spoon a little bit of chocolate into each cup of a silicone spherical mold.
Use the back of the spoon to spread the chocolate around the bottom of the mold and up the sides.
Place in the freezer for a few minutes.
Remove from freezer and repeat with one more spoonful of chocolate in each cup of the mold, spreading it up the sides, and freeze for another few minutes.
Remove the spheres from the molds.
Fill half of the molds with 2 tablespoons of hot chocolate powder and 1 tablespoon of espresso powder in each.
Take the empty half of each bomb and twist the open end in the remaining melted chocolate (there should not be much chocolate left, but you don't need much).
Place the melty open end of the empty half onto the open end of the filled half and press together. You can use the back of the spoon to paint on a bit of extra chocolate to seal any holes.
Drizzle melted chocolate of the same or different chocolate on top and decorate with sprinkles, if desired.