Chaas (gu:છાશ chhash, hi:छाछ chhachh) is a yogurt-based drink popular across the Indian subcontinent. In Indian English, it is often referred to as buttermilk. Chaas is made by churning yogurt (curds/dahi) and cold water together in a pot, using a hand-held instrument called madhani (whipper). This can be consumed plain or seasoned with a variety of spices. Chaas can be made from fresh yogurt, and the natural flavour of such chaas is mildly sweet. This type of chaas is very close to lassi, with two major differences: chaas is more dilute (with water) than lassi and unlike lassi, chaas does not have added sugar.
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