In a bowl, take yogurt. Mix in salt and cumin powder.
Add the grated carrots and mix thoroughly.
In a pan,heat oil.
Crackle mustard seeds and add curry leaves.
Pour this tempering to the yogurt mixture.Serve.
Cumin powder is totally optional but it gives nice flavor to raita. So I usually add in all my raita. If you don't have cumin powder, make your own by dry roasting some cumin in a pan and grind it. You can store this powder in air tight container for future.
Tempering is optional. If you do not want to temper just avoid it.
I used coconut oil for tempering. You can use any vegetable oil.