Could anyone point me in the direction of a properly authentic hotel-style sambar? I've probably tried ten different recipes and have yet to find one that's as good as Saravana Bhavan. I'm fairly versed I indian cooking techniques, terms and ingredients (living in the uk) and can re-create most of the other hotel-style food.

I always use spilt pigeon peas cooked in a pressure cooker and include drumstick, sambar onions and maybe dudhi if I have some. I use store-bought sambar powder (MTR), hing, mustard seeds, fresh curry leaves and a lime-sized tamarind block mixed with hot water. I've used recipes with paste made from coconut, loads of dhaniya, tomatoes and roasted spices, which was close, but not quite.

Are there any ingredients I'm missing out? What's your favourite sambar recipes?