Prepare all ingredients.

Heat 1 teaspoon of oil in a pan over medium heat.

Add mustard seeds and let them crackle.

Add torn curry leaves, grated ginger, green chilies, and cashew nuts.

Roast for a few minutes until fragrant.

Add semolina (rava) and roast until it releases a good aroma.

Set aside to cool.

In a mixing bowl, combine the roasted rava mixture with yogurt.

Add enough water to make a thick batter.

Let the batter rest for 10-15 minutes.

Add a little water to adjust the consistency as the rava will absorb moisture.

Add grated carrots and fruit salt; whisk well.

If needed, add more water to achieve a thick, dropping consistency.

Preheat an idli steamer with sufficient water.

Grease idli molds with oil.

Spoon the rava idli mixture into the greased cavities.

Place the molds in the preheated steamer and steam for 10 minutes, or until cooked through.

Test for doneness by inserting a tester; it should come out clean.

Serve the rava idli with coconut chutney and potato saagu.