The best recipe I've come across for BC is this one (it's not BIR style) and is at least on a par with any I've eaten in good (top end - not curry house) Indian restaurants, although I may well add some black salt to the marinade next time - the flavour boost to the chicken is amazing. https://norecipes.com/butter-chicken-recipe/ I normally serve it with this version of egg pilau - heaven on a plate!
Looks a top recipe O. F. The name often put me off - thinking it was a wifies choice. But a little exra ginger & chilli (not loads) = heaven. Have you tried making Indian oil. ? Check it out all the dry spice are already in and I make 1-1 1/2 litres at a time. When I take the stopper off the bottle it smells like an Indian kitchen.
1) It's really just the original Northern Indian version of chicken tikka masala. I can't recommend the recipe link I posted highly enough - even though the chef is Japanese/American there's not too much sweetness and it's full of flavour. If you decide to give it a whirl and serve it with the egg pilau I suggested you'll never think of BC and rice in the same way again. 2) I must confess to never even having thought about it. What's your recipe and what do you use it for? I do make my own Cantonese style chilli oil, for use as a dipping sauce with dim sum etc.
Sorry about the delay O. F. - grand bairns on visit. 1L neutral veg oil(e.g. rape or sunflower) fresh 2 large onions 3-4 inch ginger 4-5 garlic cloved 2-3 chillies ( can use dried) All chopped large bits Dry ( heaped teaspoons) 1 onion seeds 1 black peppercorns 1.5 fennel seed 1.5 tumeric seeds 1.5 Mustard seeds 2 Cumin seeds 3 corriander seeds Loose 2 cinnamon sticks 3-4 black cardemoms 10 green - - // - - 10 cloves powder or paste spice though good makes the oil cloudy Every thing up in a large pot, bring to boil and then dimmer at least 20 mins. (I take 30) let it cool - seive into large glass bottle (cork needed) I know most folk do not carry this range of spices (tho I think you will have most) but spacket of each spice will make, eventually, a lot of oil. I promise the smell of this oil will get your glands going. The base curry I use is just that a base to build on. Base curry the same amount as the next ingredient a tin of chopped tomates (blended smooth if you like) toss in any or none ( up to each household)of chopped fresh veg. Deffo onion, mushr. peppers owt you like goodly ladle of oil. I assume you like fresh corriander I chopp up loads of the stilk & put that in the sauce. The meat I marinate in the oil in a plstic bag overnight in fridge (if I can). Fry the meat in the oil. - then put in the sauce let it simmer as long as you like at least 1/2 - 1 hr. Serve with fredh corriander. tasting as it comes together you can udjust strength (chilli, ginger) or garlic or more garam massala or fresh corrriander etc. Give it go mate you wont regret it.
A korma would be nice if you chucked a few chillies in there, the base flavour is good it's just so bland without the heat.