I made this for yesterday's curry fest with the family and it went down really well.
Original recipe on Vivek Singhs website http://www.viveksingh.co.uk/march-old-delhi-style-butter-chicken/

I made it with boned thighs as the kids prefer it that way, if I was making it for me and the wife it would be whole thighs skinned.

2x 750g free-range young chicken (poussin), skinned and each cut in half along the backbone (alternatively use 800g boned chicken thighs cut into two)

For the marinade
120g Greek yoghurt
2 tablespoons Ginger & Garlic paste
1 tablespoon vegetable oil
1

No, some Brahmins and Jains eschew both onions and garlic and use asafoetida instead.  Whether the omission in this particular recipe is intentional is moot,

** Phil.

Made this tonight.  Really really nice.  OH who is a curry wimp said it really nice but just on the edge, so that is praise indeed.  It does have a bite and a degree of heat, which my oh isn't used to when ordering from our fav BIR.  I think I made the sauce too thin, but the rice soaked it up okay.  Maybe 150ml instead of 200ml of water next time.  As there is only two of us I letting the remainder reduce before freezing.  We made it with chicken breast chopped into chunks and then marinated overnight.  This brought out the lemon, which gave it a refreshing zing.  We accompanied this with onion bhajis and veg samosas as that's what we had in the freezer.  maybe next time a nice flaky paratha would work to help soak up the liquid..

Thanks for the recommendation.