Wash hands thoroughly, lathering with soap and rinsing with running water before starting to assemble the froyo.
Place all ingredients through salt (if using) in a high-sided container suitable for use of the immersion blender or into the bowl of a food processor.Blend for up to two minutes to puree, stopping once or twice to push ingredients on the top down and scrape any yogurt off the sides of the container.Or, use the food processor or a blender.
Stir the chopped mint into the blueberry-yogurt puree.
Start your ice cream machine. Pour the fruit puree into the machine. Once the machine has done its magic and turned the puree into a frozen dessert, serve the yogurt as soon as possible.Or, place in a storage container in the freezer. It's best to let it sit at room temperature for at least an hour before you plan to serve if it has been in the freezer overnight.
Notes
Instead of using an ice cream maker, you could also freeze the puree in loaf pans for two to four hours. Stir every 30 minutes while it is freezing to reduce ice crystal formation and improve the texture.You could also make popsicles by pouring the puree into molds, which could be just perfect for a pool party or outdoor gathering!