I was looking for a blue punch a while ago and found a few recipes, (see Turquoise Lemonade) but here is one I just saw - from Toni Spilsbury that looks good.
It might not be the perfect time of year for blue punch, but if you do a blue Christmas, it might be just right.
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When I was wanting the blue lemonade a while ago I was looking for the little packages of Kool-Aid powder in blue and couldn't find it, even online. This recipe uses the premixed gallon of juice - maybe I can find that easier!?!?!?!
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I think I'll try this someday!