hi , ive been trying to get the bir for many a year now, ive tried a few bases , kris dillon,pat chapmans and a few off the net.you speak of the secret ingredient which im not sure there is, iI feel there must be, then i think its to do with technique, im not sure but the nearest i got was an ordinary chicken curry which i seen on mamta gupta`s site in which there is the normal onion,garlic ,ginger tomato cumin,corriander tumeric .I added a few cloves cinamon stick .while on my quest i asked a few asian grocers how to make a restuarant curry and the nearest i got was to do the usual but add methi and at the end she said ( och stuff the restuarant guys) add some yoghurt at the end.Which i tried but it still wasnt right, then when on mamta gupta`s site i read about using asafoetida in dhals so i decieded to add a pinch with the cumin seeds in the oil before the onions. well the smell was there bir well nearly not too strong but there...me the other half and my daughter had it that night it was better than normal but still not the taste. The small lot which was left got put in the micro till the next night i was going to through it out but decided to heat it and try it when my wife and daughter came in they said its like a real indian in here..shame they couldnt taste it it was so good best ive ever tasted really like bir i ate the lot lol so to me the methi yoghurt and asafoetida and leaving to the next day is the answer but i need to try different amounts but i will report back when i get it perfect.
btw i asked an asian shopkeeper lots of times and got the same usual recipe without the yoghurt asafoetida and methi..when i told him about asafoetida he looked puzzled and him and his wife said they never heard of it which tells me thats part to do with the secret.
hope this isnt too long and winded but i feel if the people on here try this and experiment we will get the perfect bir