Peel and chop beetroot into small pieces.
Transfer chopped beetroot into a blender jar.
Add green chilly, ginger, mint leaves and curds.
Blend until smooth.
Now add roasted cumin powder, salt and 2 cups of chilled water.Mix well.
For tempering, heat 1 tsp oil in a pan.
Add mustard seeds and curry leaves.
When they start spluttering, pour the tempering into beetroot chaas.
Refrigerate and serve chilled.