Pureed banana gives this mixture an especially smooth texture, and orange-juice concentrate and crème de cassis add a complementary tang.
Puree blueberries in a food processor. To remove skins, force the puree through a fine strainer into a bowl.
Add bananas to the food processor and puree. Add the strained blueberry puree, yogurt, sugar, orange-juice concentrate and creme de cassis or black currant syrup and process just until mixed in. If necessary, chill until cold.
Pour into the canister of an ice cream maker and freeze according to the manufacturer's instructions. (Alternatively, freeze the mixture in a shallow metal cake pan until solid, about 6 hours. Break into chunks and process in a food processor until smooth.)
1 1/2 fruit, 1 other carbohydrate