What kind did you want to use? I've had luck with regular granulated, brown and turbinado - but I've never tried any others. I have also never added spices to any sugar destined for the torch. I think it's pretty packed with flavor and doesn't need spices. The spices may burn. I'd do a test run with the sugars and the spices - you're not exactly experimenting with truffles.
I would suggest you use your spices directly on the product then torch the sugar over it. This should give you some contrast in flavor. I have added to suger only to have the seasoning burn before the sugar came to temp. But if your going for that nutty flavor then do it that way.
good luck and let us know.