1 large sweet potato (about 1 pound) peeled and cut into 1/2-inch chunks2 tablespoons extra virgin olive oil Coarse sea salt 6 cups vegetable stock 1 large bunch mustard greens, tough stems removed, chopped into bite-size pieces 1 teaspoon mustard seeds 3 cloves garlic, minced 2 teaspoons apple cider vinegar White pepper

Preheat the oven to 425°F. In a large bowl, toss the sweet potatoes with 1 tablespoon of the oil and 1/4 teaspoon of the salt. Transfer the sweet potatoes to a parchment-lined baking dish and roast for 1 hour, stirring every 15 minutes, until they are starting to crisp on the edges.

While the sweet potatoes are roasting, bring the vegetable stock to a boil in a medium saucepan over high heat. Add the mustard greens and cook, uncovered for 4 to 6 minutes, until softened and the sulfur has been released from them. Remove the greens from the heat, drain the stock into a bowl, and set it aside.

Over medium heat in the saucepan just used, warm 1 tablespoon of the olive oil. Add the mustard seeds and cook, stirring occasionally, until they start to pop, 2 to 3 minutes. Next add the garlic and sauté until fragrant, about 1 1/2 minutes. Then add the greens and 1/4 teaspoon salt. Sauté the greens, stirring occasionally, until most of the liquid has evaporated, about 3 minutes. Add the vegetable stock back to the saucepan and set aside.

When the sweet potatoes are done, transfer them to the saucepan. Bring to a boil, then lower to medium and simmer for about 25 minutes until the sweet potatoes are fork tender. Add the apple cider vinegar and white pepper and additional salt to taste.

From theroot.com