This recipe makes 12 cups of lusciously smooth gelato--perfect for summer parties. The berry puree can be made several days in advance and refrigerated. One key step: Be sure to strain the seeds.
Place whole milk, heavy cream, sugar, milk powder, vanilla bean paste, and Blackberry Puree in a large saucepan; bring to a low simmer over medium. Remove from heat; cool completely, about 1 hour. Place in an airtight container, and chill 2 days.
Pour mixture into freezer can of a 4-quart ice-cream freezer; proceed according to manufacturer's instructions. (Instructions and times will vary.) Transfer gelato to an airtight freezer-safe container; freeze until firm, about 2 hours. Garnish servings with fresh blackberries.