My method is similar, a hotch potch of my own ideas, together with the corpus of curry books (KD etc)available and some great ideas from CrO people:
I chuck a chopped chillie into a heavy based frying pan containing 3 tbs of oil, and when it is sizzlingI know the temp is high enough to cook the raw spices without burning them (Bruce Edwards' idea this one!). I wait a further minute to allow any fried chillie flavour to develope, then I bung in garlic puree followed by (diluted) tomarto puree and cook till moisture evaporated. Next goes in spice mix, chillie powder, ground dried methi leaf (C.O. KD), salt and a tiny pinch of sugar ( most of which caramalizes in the hot oil).
After cooking the spice for a min or so, toffee aroma, then add base in stages bringing back to boil after each edition.
Instead of lemon juice I add blizzed tinned toms to sour, about 3 or 4 tbs, I believe CK (?) does this also, and a lot of chopped corriander just before serving, it does not need 'cooking-in' The finaly chopped stalks actually givce a much better flavour than the leaves ( I just use those to garnish) - slightly 'lemony' rather thatn 'candle wax'!
Might have one tomorrrow!!