Pressure cook the thurdal and smash it nicely and keep it aside. Take the pepper and cumin seeds in a mixer
Grind the pepper and cumin seeds to a coarse powder
Take 3 pine apple rings separately. If you have the whole pineapple, peel the skin and cut the pineapple into circles
Chop the pineapple to bigger pieces and add it to the mixer
Grind the pineapple pieces to a nice paste
Take 1 tomato and nicely mash it. Or you can even give a pulse in the mixer to make a puree
To the tomato puree, add 1 cup of water, salt, turmeric and ½ quantity of ground coarse pepper-cumin powder, ground pineapple paste and rasam powder and allow the tomato puree to cook well
Meanwhile, finely chop the rest of pineapple pieces and tomatoes and keep it ready
In a separate pan, add ghee and add mustard seeds when the ghee is hot, when the mustard seeds starts to sputter, add broken red chilli, hing, rest of the ground pepper-cumin powder and curry leaves and saute it for 20 seconds
Add the chopped pineapple and tomato pieces and saute it for 2 minutes in a medium flame
Add the seasoned ingredients along with sauted pineapple and tomato pieces to the boiling tomato puree
Add the mashed dal and mix well.
Add 2 cups of water and keep the flame in medium till we get a froth. Finally garnish with coriander leaves and remove from flame
The delicious and spicy pineapple rasam is ready to serve.