Prep: Wash and rinse toor dal and chana dal. Soak for 10 minutes while prepping other ingredients. Quarter the onions and tomatoes.
Add ingredients: Drain the water and add dals, onions, tomatoes, coriander powder, asafoetida, and half the water to the Instant Pot or pressure cooker.
Pressure Cook: Cook for 8 minutes and do a quick pressure release.
Blend: Use a hand blender to make the mixture smooth.
Add remaining Ingredients: Add chopped vegetables, coconut, cilantro, curry leaves, sambar masala, jaggery, tamarind pulp, and remaining water.
Simmer: Turn on sauté mode and bring to a boil. Reduce heat and simmer until vegetables are soft.
Adjust: Taste and adjust seasoning or consistency as needed.
Tadka: Heat oil or ghee in a small pan. Add asafoetida, mustard seeds, and whole red chilies. Once they sizzle, pour the tadka over the sambar and mix well.