Take 2 tsp curd and some shallots and green chilli (after keeping 3 - 4 nos. of shallots and 2 green chillies aside) and grind them well in a grinder mixer.
Then add this paste into the diluted curd (Butter milk) along with required quantity of salt and stir it well and keep it aside.
Heat oil in a cheenachatti and burst mustard seeds in this hot oil. Then add red chilli pieces and curry leaves into this hot oil and stir it well.
When colour of these ingredients turn into golden/brown, add the diluted curd (Butter milk), stir it further and heat it for about 2 - 3 minutes. Put off the stove before boiling starts and keep the mix separately.
Heat some oil again and add chopped shallots, garlic, cumin seeds and fenugreek seeds into this hot oil and stir it well.
When colour of the shallots, garlic, cumin seeds and fenugreek seeds turn into golden, add turmeric powder, red chilli powder, asafoetida powder and salt (if necessary) and stir it well.
After about 1 - 2 minutes, put off the stove and add this fried mix into the already heated and kept diluted curd (butter milk).
Ulli Kachiyathu (Palakkadan Style) is ready. This can be served with Dosa/Idly/Boiled Rice etc.
Notes
You can visit this link Moru Curry With Coconut. You can also visit this link Kumbalanga Moru Curry.