Today I was looking for a non-dairy shake that used cranberries, since I have a surplus of those at the moment. This is what I came up with that worked very well:
2 mandarin oranges
3/4 cup cranberries
2 tbsp cocoa powder/sugar mix (I used Starbucks hot cocoa mix)
Blend to desired consistency
The cranberries are very tart, and when I initially tried the shake without the cocoa/sugar mix, it didn't work for my taste (the oranges weren't sweet enough to compensate). Adding the cocoa/sugar mixture was the perfect solution.