Scrap the skin of yam. Chop them into bite sized pieces. Set aside. Rinse it well to get rid of mud and dirt.
After cutting soak in water sot hat it doesn’t turn black. Make sure to grease your hands with oil so that it doesn't itch.
Add turmeric powder along with salt as required. Cook it.
Meanwhile rinse cow peas, pressure cook for 4 whistles or until soft.
In a mixer add all the ingredients listed under ‘to grind’.
Add little water grind it to a semi fine paste.
By now yam must have cooked, cook until soft enough to mash.
Mash it roughly with a ladle. Set aside.
Dry roast coconut until golden brown. Set aside.
Now add coconut paste along with little water and let it to boil.
Add required salt.
Cook until it starts to thicken, then add cooked cowpeas and cook in low flame.
Prepare the tadka – Heat oil add the ingredients listed under ‘to temper’ add onion only after the items splutters.
Fry till onions turn transparent.
One it becomes thick, add the tadka and roasted coconut, combine and let it cook for a minute. Switch off.
Serve Erissery hot with rice and papadam.