In a large bowl, mix the powdered sugar, melted butter, sweetened condensed milk, and mint extract with a large wooden spoon (you may have to use your hands towards the end) until smooth. Fold in green food coloring and chopped chocolate until combined.
Refrigerate uncovered for about 30 minutes, then roll into balls with damp hands and place on cookie sheets lined with wax paper. Refrigerate again for about an hour.
Melt almond bark according to package directions. Dip the candies in the melted chocolate, shaking excess chocolate off gently. Place back on lined cookie sheets. Using a fork, drizzle any leftover chocolate on candies and refrigerate until firm.