Catching up with this.
RD
Bengali BIR Rogan Josh is a 2 stage dish or a combined/layered curry.
Here in the Northeast its usually a Bhuna style cooked curry with a sweet/spicy Tomato and onion top.
It is the caramelised Tomato top that defines and separates the dish from others on the menu.
This is BIR cooking, Nothing to do with traditional Indian textbook recipes, I've never known it cooked differently in 40 years of currying.
If its not broke, don't fix it ;D
Also this Rogan style of cooking has spurned a few other layered dishes consigned to the Chef's Specialities part of the menu.
But if you don't like Tomatoes, a Rogan Josh is one to avoid.
E.G. In my video recipe, I used 3 medium sized tomatoes.
Anyhoo, glad the vid inspired you to cook a tasty curry, your photo looks like a good meaty Bhuna.
My TaskRD set my task to do my take on a Nihari Curry, BIR style.
I had some precooked Lamb and Beef, fresh Mushrooms and Chillis.
(The Indian flavour enhancers are Whole Garam Spices and SHAN Nihari spice mix.)
So I set about with my tried, tested and refined recipe.

First in the pan, hot oil, Whole Garam Spices.

Add a good handful of service onions

Add 3 chopped mushrooms.

Add 2 sliced Habenero chillis.

Add 3 tbs of Tomato Puree dilute, 0.5 tsp mixed powder, 0.5 tsp chilli powder, 1 heaped tsp of
Shan Nihari powder.
Add precooked meat and a ladle of curry base (Garabi) and cook.

Add more Garabi and cook.

Add fresh Coriander and a quartered Tomato and cook.

Serve and Garnish

Enjoy this dish, spicy, full of traditional Indian flavours, cooked BIR style, in around 12 minutes.
(It may be obvious to some, but don't eat the Garam Spices)
cheers ChewyTikka