Place a pan on medium flame add oil, roast mustard seeds,urad dal,coriander seeds, cumin seeds, fenugreek seeds and red chillies for few minutes.
Put the above into a mixer jar,add turmeric,garlic,onion and coconut and grind to a fine paste. Keep this aside.
In a big vessel put 3 cups water,add tamarind and squeeze till well mixed ,add jaggery and chopped thouthe and cover and cook this till thouthe is almost done.Now add the above ground coconut masala paste and salt and mix well and cook for 5 to 8 minutes.
In a small place add oil,when hot add mustard seeds and urad dal,when mustard seeds pop add crushed garlic,curry leaves and red chillies.fry till the garlic turns brown.Pour over the thouthe kodel.
Serve with rice.