While I have always been somewhat of a sweet potato addict, I prefer savory preparations to the traditional brown sugar and maple syrup concoctions typically found on the Thanksgiving table. I originally got the idea for these potatoes from Marcus Samuelsson, chef and co-owner of Aquavit in Manhattan. A few years ago, he teamed up with Slow Food to give cooking lessons to some of the students at The Children's Storefront, an independent tuition-free school in Harlem. I happened to be there observing one afternoon when he taught the kids his version of the recipe, and I have been making my own adaptation ever since. I hope you'll find the combination of sweet potatoes, crème fraîche, garlic, herbs and parmesan as rich and satisfying as I do. —Merrill Stubbs
Peel the sweet potatoes and cut them into 1-inch cubes. Put the potatoes in a saucepan with the milk, cream, thyme, bay leaf, garlic clove and a pinch of salt. Bring to a boil over high heat, then lower the heat and simmer for 20 to 25 minutes, until the potatoes are tender when pierced with a knife.
Drain the potatoes, reserving the cooking liquid, and return them to the saucepan. Mash the potatoes using a potato masher or a ricer. While the potatoes are still warm, stir in the butter, crème fraîche and parmesan cheese. At this point, stir in some of the cooking liquid—a little at a time—until you reach a good consistency. Add more salt and pepper to taste. Cover the potatoes and keep warm until you're ready to serve them. (If you are planning to reheat the potatoes, you can save the rest of the cooking liquid to prevent them from drying out.)