Make a 9x13 pan of brownies according to the directions on the box. DO NOT overbake.
Allow brownies to cool completely in the pan.
Use a fork to break up the brownies. You can trim off the edge pieces if you'd like, or just mash them into the mixture.
Press small portions into silicone molds or roll into tiny balls and place on a parchment lined baking sheet.
Freeze brownie shapes for 60-90 minutes.Tip: If you are making shapes using silicone molds, it can be quite time-consuming if you only have a couple of molds. I freeze mine for 30 minutes, then transfer the shapes to a baking sheet to freeze for another hour. That way, I can get started on the next batch of heart shapes. Making a combination of shaped truffles and round truffles works great and takes less time than making them all shaped like hearts, etc.
Heat melting chocolate in the microwave for 60 seconds (heat in 30-second increments). Stir until completely melted.Note: This is is you are heating an entire bag of melting chocolate. If making a variety of colors, and heating up smaller portions, heat for 15 seconds at a time and stir in between each interval.
Pop the brownie truffles out of the molds.
Dip brownie truffles into melted chocolate and coat both sides. A fork works great to flip the truffle over in the chocolate. If making round truffles, I highly recommend using a dipping tool.
Tap the fork against the side of the bowl to allow some of the excess chocolate to drip off. You can also slide the fork across the edge of the bowl to remove excess chocolate.
Place dipped truffles on a parchment-lined sheet (if the truffle doesn't slide off easily, use a second fork push it onto the sheet) and immediately add sprinkles. The truffles will set up FAST since the centers are frozen.
Video
Notes
The number of truffles that this recipe yields will depend on the size that you make them. I made 52 truffles. The hearts were 1" wide and the round truffles were rolled into tiny ¾" balls. You can store the truffles on the counter, in the refrigerator, or in the freezer.