1 14oz can sweetened condensed milk
3 tablespoons unsweetened cocoa powder
1 tablespoon butter (add a pinch of salt if using unsalted butter)
In a medium saucepan, heat condensed milk, cocoa powder, and butter over medium heat. Stir constantly until the mixture has thickened, about 10 minutes. Remove from heat to cool. When the chocolate mixture has cooled enough to handle, use a cookie scoop or rounded tablespoon to scoop out. The mixture will still be extremely soft and gooey, so to make it easier to roll into balls, drop the mixture directly into a shallow bowl filled with the chocolate jimmies; use one hand to roll around in the chocolate jimmies, shaping into a ball as you go. Once the chocolate is covered in the jimmies, roll between your palms to form perfectly round bon bons. Refrigerate to set, and enjoy!