We have all cooked this dal at home.

In the south sambhar is made from it. 

In Awadhwe boil it with a pinch of haldi and salt to taste.

It’s consistency is thick.

It’s garnished with diced cloves of garlic and whole red chilli. These are heated in an iron skillet ( small size) and then put inside the dal pot so that the iron taste ( sondhapan) may come into the dal.
Now the dal as cooked in bygone years in the imperial city of Shahjahanabad.

1 kg Dal e arhar

250 Gm dahi 

1 maasha each laung ( clove) and elaichi ( cardamom) A masha is a traditional Indian unit of mass, now standardized as 0.97 grams (0.034 oz)

Salt to taste

250 gm Ghee 

125 gm onions

Lahsan ( garlic) & adrak ( ginger) 1 chitank (15 gm)

Mitch siyah aur surkh( pepper corns & red chilli) 3 maasha each

1 maasha zafran ( saffron)
Juice of lemon 1 chitank ( 15 gm)

1. Boil the dal well – called “dal Ko khoob achhi tarah josh dijiye)

2. Throw away water and boil again, adding salt to the water

3. Throw the water again

4. Add juice of adrak and dahi to it and leave for one hour to marinate

5. Grind the garlic, pepper and chilli  and strain through a Muslin cloth.

6. Add the masala and dal e arhar to ghee and fry. Keep adding dashes of water till the dal is well cooked and tender.

7. Put on dum ( this means putting the pot of dal on a heavy tawa so it doesn’t burn) for 15 min

8. Mix it well and add lemon juice to it. Consistency will be thick. 

9. Fry finely sliced onions till golden brown in ghee. 

10. Add zafran and garnish with the fried onions and serve.

Note :haven’t tried it myself. Just copied recipe down from an old recipe book