I just use left over coffee... you know ... from the guests who say yes they would like another cup and you put a fresh pot on, and then they decide they have had enough.
I put it in the fridge and enjoy it over ice cubes and mix in some milk. A few less calories, but it is nice in the afternoon. It is not counted as part of my only 2 cups a day ration coz it is cold and left over.

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