For an extra cold smoothie, partially freeze the yogurt and orange juice before blending. For variety, try apple juice instead of orange or other fruits could be used instead of berries. When fresh blueberries, blackberries, and raspberries are in season, buy extra and freeze them in small containers to use in recipes like this one.
2 cups frozen berries
1 cup fat-free plain yogurt
1/2 cup orange juice
1/4 cup fresh spinach
Blend all ingredients together in a blender until smooth. Serves 4.
Recipe adapted from allrecipes.com