Candied Yams

1 pound unsalted butter
2 pounds sweet potatoes, peeled and coarsely chopped
2 cups water
1 cup Chef Paul Prudhomme's Sweetie Magic®
1 cup packed dark brown sugar
⅔ unpeeled orange, sliced and seeded (stem slice discarded)
⅔ unpeeled lemon, sliced and seeded (stem slice discarded)
1 tablespoon vanilla extract
½ teaspoon salt

Heat the butter in a 4-quart saucepan over high heat; when about half melted, add the remaining ingredients. Stir, cover and cook over high heat until mixture comes to a strong boil, about 10 minutes. Stir, then reduce heat and simmer covered for 20 minutes. Uncover and continue cooking until sweet potatoes are very tender, about 20 minutes, stirring occasionally. Remove from heat and serve immediately, undrained.