What you'll need:
a box of chocolate cake mix (and whatever it says you need to make the cake)
a tub of chocolate frosting
a LOT of dark chocolate chips (probably two bags)
icing in a the color of your choice
Bake your cake according to the box instructions.
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Roll into little balls.
Heat up your chocolate to 120 degrees in the microwave, and then let it cool to about 95 degrees. (This is called "tempering;" it makes the chocolate harden a little more cleanly.)
Dip the balls in the chocolate and then set them on wax paper to cool and harden.
Once dry, decorate!