Firstly, peel and chop cucumber into small pieces.
Transfer chopped cucumber to a blender jar. Add chopped green chilly, grated ginger, mint leaves, fresh coriander leaves and curds.
Blend until smooth.
Now,add 2 cups of chilled water, salt and roasted cumin powder. Mix well.
Refrigerate and serve chilled.
Notes
You can also add a tempering to this buttermilk. For the tempering, heat 1/2 a tsp oil. Add mustard seeds and curry leaves. When the seeds crackle, pour the tempering into the butter milk.Variations can be made by replacing cucumber with beetroot. Spices like black pepper powder and black salt can also be added.