Combine the blueberries and 2 tablespoons sugar in a medium-sized saucepan over medium heat. Stir a few times as the berries begin to simmer.
Reduce the heat to medium-low and let the berries cook, stirring occasionally. The berries will burst as they simmer. When the mixture has thickened and reduced to about 1 cup’s worth of berry sauce, about 8-9 minutes, remove from the heat and cool completely.
Gelato Instructions
Whisk together the milk, cream, sugar, vanilla extract, and salt. Add ⅔ cup of the blueberry sauce and whisk to combine. (Set aside the remaining blueberry sauce to use as an ice cream topping.)
Pour into the ice cream machine and freeze according to the manufacturer's directions for gelato. Transfer to an airtight container and freeze until firm. Allow the frozen gelato to warm at room temperature for a few minutes before serving.