Revisited this one today, after having had it a couple of times from TA since the last time I tried. The pic looks much like the others I guess, but here it is anyway:

I got the lamb just about right this time (which was a biggie for me). Similar to what Lou posted - leg cut into large chunks and slow-cooked for two hours.
I also made a few little alterations, adding very finely chopped onion and green pepper, plus some almond powder towards the end (and a little chilli powder to lift it).
It's a really nice curry; but, to be honest, it's not what I'm aiming for - which is to recreate the TA version. I'm beginning to think that the Tandoori Masala is possibly taking the flavour in the wrong direction.
Anyway, if anyone is interested, here is the updated (but not finalised) recipe :
Basanti Ingredients :
2 tbsp Vegetable oil 1 tbsp finely chopped onion
1 tbsp finely chopped green pepper
1/4 tsp asafoetida 1 1/2 tsp mix powder 1 1/2 tsp garlic/ginger paste 2 tsp onion/chilli puree 6 tbsp tomato paste 4 ladles base sauce 1 tsp tandoori masala 1 portion of pre-cooked lamb/chicken 1 1/2 tsp methi 1 tsp salt 1 tsp sugar 2 tbsp roughly chopped coriander leaf 1 tbsp Mother's Recipe Mixed Pickle (or similar) 1 tsp ground almonds
Method : Heat oil in preferred cooking vessel (not too hot). Gently fry chopped onion and pepper until softened.
Add spice mix and asafoetida and stir for 30 seconds or so Add garlic/ginger paste and stir for 30 seconds or so Add onion/chilli paste and stir for a minute Add tomato paste and Tandoori Masala and cook out for a few minutes, adjusting heat as necessary. Add salt and sugar and stir in Add two ladles of base and pre-cooked meat and simmer until reduced by about a third. Add 1 1/2 tsp of methi leaf and a good tbsp of chopped coriander leaf and stir well Add another ladle or two of base, pickle and ground almonds, and reduce to desired consistency - should be thickish.
Notes : 1/ My ladles are 100ml. 2/ Mix powder is: 2 parts ground cumin 2 parts paprika 2 parts ground fenugreek 1 part ground coriander 1 part Garam Masala. 3/ Onion/Chilli puree is half an onion and two bullet chillies pureed. 4/ I use TRS Tandoori Masala which contains natural food colouring, but add a little red if you like. 5/ My tomato paste is one large tin of blitzed plum tomatoes, with around 75ml water and a large tbsp of tomato puree.