One of my favourite Indian curries is Rogan Josh. Rogan Josh is a Kashmiri curry, and there are many variations on this traditional dish, with some being high fodmap and some being very low fodmap. Your luck may vary considerably depending on how your local restaurant does the dish. For instance, this version of Rogan Josh uses 1kg of onion! (and is obviously extremely high fodmap) - however, these recipes use no onion. I have also seen recipes that add tomato, yoghurt or cream.
I’ve borrowed from all of these recipes, to make a variant that is low fodmap, gluten free and lactose and casein free, with ingredients I was able to find relatively easily (this may vary depending on what your local stores offer when it comes to Indian spices). I did not have any Rajantot (which is used in several of the recipes I found online), so I did include a small amount of tomato. This can be changed if you have problems tolerating even a small amount of fresh tomato.