In a small bowl, use an electric mixer to beat together powdered sugar, cocoa powder, butter, and whiskey.
Once the ingredients are thoroughly combined, refrigerate for 30 minutes.
Once 30 minutes are up, remove from the fridge. Line a baking sheet with wax paper
Scoop out portions of the batter with a spoon or a small cookie scoop and roll into 2 inch balls. Set carefully on wax paper. Freeze for at least 10 minutes.
While the truffles are freezing, place pecans in a sandwich bag. Use a rolling pin to break them into fine pieces. Place the chocolate chips in a small bowl and melt in the microwave in 30-second intervals, stirring between each interval.
Remove whiskey balls from freezer and dip each one into the melted chocolate, using a fork to assure that each one is completely coated. Place them back onto a lined baking sheet and top with finely crushed pecans.
Place back in the freezer for about 20 minutes. Then remove and serve