Very Berry Frozen Yogurt

I was planning to make a batch of Strawberry Frozen Yogurt from Lick It! Creamy Dreamy Vegan Ice Creams Your Mouth Will Love . . . but didn't have enough strawberries, so I came up with this one and it was GOOD!

Very Berry Frozen Yogurt
The berries can be fresh or frozen.
Makes 1 quart

1 (32-ounce) tub of vanilla yogurt (2 1/2 cups) -- can be dairy or nondairy yogurt
1 cups halved strawberries
1/2 cup blueberries
2/3 cup raspberries
2 tablespoons granulated sugar or agave syrup, if needed

Combine the yogurt and berries in a blender and process until smooth. Sweeten with the sugar to taste, if needed. Freeze in an ice cream maker according to the manufacturer’s directions.