Sometimes I bake them just like I would a regular potatoe, so they get that nice crusty skin and all soft on the inside. A tiny pat of butter and some S & P finish them off nicely.
My favorite way to make them is to peel them and then slice into rounds about 1/4 inch thick. Toss with EVOO and salt. Roast at 450 for about 30 minutes. Then add some sweet onion wedges. Stir 'em up and add a dash more EVOO for the onions if necessary. Roast for about 20-30 minutes more. Again, a little S & P is all I use to finish them off before digging in.
Mashing them is also a great idea! A dash of butter is yummy in them that way.
I think the sweet of the potato is enough so I'm not huge fan of adding maple syrup. But that's how I used to get my son to eat them! =P The things we will do to get our kids to eat vegetables...
The cinnamon and nutmeg ideas sound nice. I think I'll try that next time.