I had not come across this, which appears to be a chain out of India from the Leela group. Looks good!
Though the Malvani prawn curry you ate wouldn’t have any hint of sweetness in it as there is none in that regional style – but if you had a prawn malaikari from Bengal, it would definitely have a sweet tinge from both onions and sugar 
(in line with @medgirl’s comments above).
