My dad's first line when mum starts cooking sambar is ' sambar inge ukkarungo' :) He is the biggest sambar fan in the planet. He appreciates me trying new versions of the classic like palakkadan, kozhikkodan etc etc. My son has taken to his appappan's palate and luvs sambar esp if it's with dosa. I can virtually eat it with anything at all - rice, dosa, idli, upma, idiyappam and chapati.
A variety of vegetables can be used in an avial, which includes drumsticks, yam, raw banana, ash gourd (kumbalanga), aubergine (vazhuthananga) and more recently carrots, potato and cucumber.
Ideally sambar needs to be cooked in an open pot which takes a lot of time. I go for the quick pressure cooker version when I have less time. I know daddy this version is not ur favourite. :(
