In a small bowl, stir together ice cream and extract until blended. Freeze until firm, at least 2 hours. Meanwhile, line a baking sheet with parchment paper and freeze alongside.
Using a large melon baller, quickly scoop all the ice cream into balls and place them on one side of the cold baking sheet. Freeze until firm, 1 to 1 1/2 hours.
Insert a decorative skewer or pick into the center of each ice cream ball and return to freezer to set, about 30 minutes.
Meanwhile, put chopped chocolate and shortening into a small metal bowl. Set bowl in a slightly larger bowl of hot water and let sit until melted, stirring occasionally. Transfer chocolate mixture to a 1-cup glass measuring cup. Put crushed candies on a small plate.
Working with 1 ice cream ball at a time, dip into melted chocolate to coat, making sure chocolate reaches above ice cream onto the skewer and letting excess chocolate drip off bottom. Roll ball in candy and set on the clean side of the baking sheet. Repeat with remaining balls, returning them to the freezer if they start to soften. Freeze at least 2 hours before serving.
Bonbon Variations: Experiment with other flavors of ice cream, such as coconut or chocolate, and coatings, such as flaked coconut or dark chocolate.
Note: Nutritional analysis is per bonbon.