I came across this idea for roasting vegetables in coffee beans while reading the January 2012 issue of Food & Wine magazine. The issue featured a recipe for Coffee-Baked Squash with Crème Fraîche by Chef René Redzepi of Noma and Daniel Patterson of Coi (whom the magazine refers to as “two of the world’s best chefs”). I took their technique and applied it to a winter root vegetable with similar characteristics: jewel yam (sweet potato). I filled a baking pan with an inexpensive bag of coffee beans, nestling in the sweet potatoes. After an hour roasting, the sweet potatoes collapsed in their skins, piping hot and tender.Cutting them open released a subtle aroma of earth and spice, with just a hint of freshly brewed coffee essence. I chose to compliment these notes with a sprinkling of smoked paprika, brown sugar, and cayenne pepper. For garnish, crème fraîche contributed a bright tang, lime zest a floral character, and cilantro a fresh, green flavor. Quantities aren’t too important here, so feel free to ad lib based on the spices and herbs in your pantry. My flavor profile was influenced by Mexican and Spanish ingredients, but you could go with curry spice (India), or woodsy rosemary and mascarpone (Italy). —la domestique
Preheat the oven to 375 degrees Fahrenheit. Pour the coffee beans into a baking sheet. Prick the sweet potatoes all over with a fork and then nestle them into the coffee beans. Place the baking sheet into the oven and roast for 30 minutes, monitoring occasionally to make sure the beans are not smoking. If the oven is too hot the coffee beans will smoke and give off a burnt aroma to the sweet potatoes.
After 30 minutes, turn the sweet potatoes over and stir the beans a bit. Turn the oven temperature down to 350 degrees Fahrenheit and continue baking the sweet potatoes until very tender and collapsed in their skins, about 30-45 minutes more. Test the sweet potatoes for doneness by piercing all the way through the flesh with a table knife. Set the sweet potatoes aside until just cool enough to handle. Once the coffee beans have cooled they can be discarded.
Make the spice mixture. In a small bowl, stir together the sea salt, smoked paprika, ground cinnamon, cayenne, and brown sugar.
Now prep the sweet potatoes as you would a baked Russet potato. Slice each potato in half lengthwise and use a fork to fluff the flesh. Sprinkle the spice mixture amongst the 4 sweet potato halves. Garnish each with a tablespoon of crème fraîche, a few pinches of lime zest, and some cilantro leaves. Serve warm potatoes immediately.