Mattha is a beverage based on buttermilk or yogurt, to which sugar or spices are added, depending on the preferred flavors. Thought to aid digestion, mattha is a beverage that is usually enjoyed before a meal or after it, but it is not unusual for it to be served during a meal as well. This beverage is somewhat similar to chaas, but it is spicier than it and slightly thicker. It is said that mattha started to be made due to the fact that the liquid which remained after the churning of butter was consumed back in the day as a treatment for stomach issues. But, besides this, this liquid was also seen as a way to refresh the body when the weather outside was hot. Thus, Indian buttermilk began to be spiced, with salt, black pepper, ginger, honey, roasted cumin seeds, and others, and enjoyed as a flavored beverage. It can even be smoked and served this way, so there are quite a few recipes for making this particular drink.
To make mattha at home, you can prepare buttermilk yourself, out of yogurt, or you can use buttermilk that can be found in stores. Still, if you use store-bought buttermilk, you will have to add a bit of water to it, for slightly thinning its consistency a little. But you can also use yogurt without making buttermilk out of it, mixing it with water and spices. Thus, for 1 cup of yogurt, you need 2 cups of water and spices to taste. You just need to put all the ingredients in a blender and mix until they form a uniform composition. You can use freshly chopped coriander leaves for its decorative aspect and flavor when serving mattha. Just make sure to check its taste before taking it out of the blender, to make sure that everything is just right.