Heat 3 tablespoons of oil in a pan over medium heat.

Once the oil is hot, add 1 teaspoon of cumin seeds, 1 teaspoon of mustard seeds, and 0.25 teaspoon of asafoetida. Sauté until the seeds start to crackle.

Add 1 medium chopped onion and sauté until it becomes soft and translucent.

Make a paste with 1 inch ginger, 4 cloves garlic, and 4 green chilies. Add the paste to the pan and sauté for a minute until fragrant.

Add 0.5 teaspoon of turmeric powder and salt to taste. Mix well.

Pour in 1.5 cups of water and bring to a boil.

Gradually add 1 cup of besan (chickpea flour) to the boiling water while stirring continuously to avoid lumps.

Cover the pan and cook the mixture for about 4-5 minutes, stirring occasionally until the mixture thickens and becomes dough-like.

Grease a rectangular mold with oil.

Pour the cooked mixture into the greased mold. Smooth the top and sprinkle fresh grated coconut and chopped coriander.

Allow the mixture to set for 1-2 hours until firm.

Once set, cut the vadi into diamond-shaped pieces and serve.