Not everyone at your party will be drinking alcohol, even if it's a kids-free event. Providing booze-free drinks for your guests is just good hosting. One fun way to impress your guests is with house-made sodas.
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And when preparing a drink menu for parties, I'd feel like a schmuck if I overlooked the non-drinkers or the designated drivers in the crowd, assuming they'd be fine with a glass of soda while I'm working up a sweat making harder drinks for everyone else. These books should provide a lot of fresh fodder for alcohol-free drinks; so can you.