I usually prefer to talk up local haunts rather than national chains, but I'm making an exception for Surf City Squeeze because, well, I love their smoothies. They make their drinks using their own non-dairy smoothie base, that I'm pretty sure may contain heroin, because I can't get enough.
My favorite is the blueberry-banana smoothie with added boosts of protein powder and spirulina, but you can also get an au natural kick from the additions of ginseng, brewer's yeast, bee pollen and other boosters. Other SF locations include Powell Bart Station and Embarcadero 3.
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