Step 1

Put the berries and sugar in a saucepan and bring to a boil. Turn the heat down and cook for about 5 minutes, just until the berries have released juice and softened.

Step 2

Puree the mixture. I used my Vitamix blender for an extra smooth puree. Refrigerate the puree until chilled.

Step 3

Blend together the sour cream, the cold blueberry puree, and the lemon juice, if using, until completely smooth.

Step 4

Process the mixture in your ice cream machine, according to the manufacturer's directions. Mine takes about 20 minutes to get to a soft serve stage.

Step 5

Spoon the soft ice cream into a loaf pan or plastic tub, cover tightly, and put in the freezer to firm up. I like to leave it for at least 5 to 6 hours.