Clean & wash 1-1/2 kg mutton n marinate with ginger-garlic paste.
Wash & peel 15 medium or 12 big Alfanso mangoes (I used 12 big ones). (Normally these are cooked whole but I prefer cutting slices from 2 sides for 2 reasons – one coz now a days there’s no guarantee of ripe mangoes being good from inside [please see collage in comments] so can’t take a risk & secondly we don’t prefer whole mangoes in this dish. We like it mixed with onions & it’s easier to eat. Use all seeds too).
Peel & wash 1 kg baby onions. Insert slits horizontally keeping onions whole (see the collage in comments) (they get separated while cooking).
Heat enough oil in a large pan. Add 2 inch cinnamon & other whole spices (black pepper, cloves) & saute. (My family doesn’t like whole spices hence I use only whole cinnamon & spices powder in place of other whole spices).
Add 6-8 medium finely sliced onions. Fry till they turn golden brown.
Add 1 tbspn ginger-garlic paste. Saute for 2 mnts.
Add 1 tspn haldi/turmeric powder, 1-1/2 tspn jeera/cumin powder, 2-1/2 tspn dhaniya/coriander powder & saute for half a minute.
Add puree of 6-8 medium tomatoes. Saute till water from tomatoes evaporates.
Add 1-1/2 tbspn or as per taste red chilli powder, 1 tspn pepper powder, 1-1/2 tspn parsi sambhar masala, 3 tspn garam masala powder (powdered whole spices. Please skip this if you are using whole spices), salt as per taste & saute for 2-3 mnts.
Add mutton, mix & fry for 5-7 mnts.
Add slit baby onions & mix.
Add mangoes & mix.
Transfer to large cooker & without adding any water close the lid & cook on high flame till first whistle. Lower the flame & cook for about 20 minutes or less/more (depends on how tough or tender the mutton is).
Remove from fire & let it cool.
When cool transfer to the pan & adjust spices if need be & if liquidy cook till it reaches d right consistency.