*the above buttermilk pie is worth selling your soul for. this has been an unsolicited advertisement*

Candied yams can be done deliciously using honey and orange juice, or brown sugar and cider. No butter necessary.

What the problem with the mashed potatoes? You don't HAVE to make them with butter or cream you know. You can use boullion to thin them a bit, and some turkey grease to add richness. serve them with gravy rather then butter.