Soak a small sized tamrind ball in 3 tbsp of water for 15 minutes. Then squeeze the tamrind and take the water alone to make the kootu.
Cut the vegetables, make the spice powder and the coconut paste for the kootu.
Wash the dal in water and add it to a pressure cooker along with 1/8 tsp turmeric powder and enough water, to cook the dal. Let it cook with the lid on for 5-6 whistles.
Let the pressure release naturally. Once cooked, whisk the dal a few times to break it and set aside.
In the same pressure cooker add some water (refer notes), 1/4 tsp turmeric powder, salt as required and the cut vegetables. Cook it for 4-5 minutes on a high flame with the lid on. (the lid need not be locked)
When the vegetables are cooked, reduce the flame and add the cooked dal and stir well.
Add the ground coconut paste to it and stir well.
Add the tamrind water to the pressure cooker and mix well. Let it cook in a medium flame for 5-7 minutes.
Now, add the spice powder and stir well. Cook for 1 more minute and switch off the stove.