I kept the skin on for mango, but I think it's better to remove the skin and use the mango.
Also after adding chilli powder, fenugreek and asofetida to the mango mixture, do a taste test. If you dont get the flavours, you can add a bit extra of the same along with mustard and dry red chilli.
The original recipe doesnt use vinegar, but I added it for a slight tangy taste.
In the original recipe, it's mentioned that the oil tends to become foamy/ bubbly after adding to mango, but nothing like that happened for me. If it becomes bubbly for you, just keep stirring it, till the bubble subsides.