Time to get the icecream maker out again

Mmm - I was wondering what to do with all the frozen blackberries in the freezer and hey presto this blackberry recipe was just sent to me to put up on our Intranet at work.  Will feed it to the five Melbourne uni geology students who are staying with us for a week.
Blackberry Icecream
Ingredients:
• 2 cups blackberries, about 12 ounces
• 1 cup granulated sugar
• 1 1/2 tablespoons lemon juice
• 1 1/2 cups heavy cream
• 1/2 cup sour cream, full fat
Preparation:
In a large saucepan over medium heat, cook blackberries, sugar, and lemon juice until sugar is dissolved and berries are soft. Put the berry mixture in a blender and puree for about 1 minute. At this point, you might want to put the puree through a mesh sieve to remove the seeds. If you do remove the seeds, return the mixture to the blender. Add heavy cream and the sour cream and pulse a few times. Pour into a bowl and chill thoroughly. Freeze in your ice cream maker following the manufacturer's directions.