Melt butter in a medium saucepot over medium heat. Once butter has melted, add the salt and peanut butter and stir until peanut butter has combined with the butter. Remove from heat.
Meanwhile, add the M&M's to a food processor and pulse until candy is crushed into tiny bits. Transfer M&M's to a large mixing bowl and mix with the finely chopped SNICKERS®, rice cereal and powdered sugar. Stir in the melted peanut butter and butter mixture until fully combined.
Begin shaping the peanut butter mixture into 1-inch balls or mini footballs and transfer to a baking sheet lined with parchment paper. If you desire some truffles NOT dipped in chocolate, immediately roll the formed balls in sprinkles or crushed candy and transfer to the baking sheet. Transfer baking sheet to the freezer and allow peanut butter balls to cool and harden for at least 30 minutes.
When peanut butter candy balls have cooled and hardened, prepare the melting chocolate. Add 1" of water to one medium saucepan over low heat. Bring to a very gentle simmer- do not boil! Place a heat-safe bowl on top of the pot (I use a glass bowl) so that the bottom of the bowl is not touching the water. The idea is that the steam generated from the water will slowly warm the bowl. That said do NOT allow steam to escape from the pot, if possible, as this is not good for the chocolate (tip- place a small towel between the pot and the bowl but be very careful as you don't want the towel to catch on fire). Add the chocolate to the bowl and gently stir with a wooden spoon or rubber spatula until chocolate is fully melted. Remove from heat.
You can also melt the chocolate in the microwave (however, I've had very bad experience with this), by placing the chocolate in microwave-safe bowls at 50% power for 30-second intervals, stirring after each.
Dip each peanut butter candy ball or football in chocolate and return to the baking sheet lined with parchment paper. Before chocolate sets, sprinkle with crushed candy pieces or colored sprinkles, if desired.
Once all peanut butter and candy balls have set completely, use a small frosting pen to draw the football stitching on each ball.