Rachael Ray has several recipes available for candied yams such as maple-orange sweet potatoes and Steve's mashed sweet potatoes with marshmallows. Yams and sweet potatoes can be used interchangeably in these recipes.
To make the maple-orange sweet potatoes, boil 4 pounds of sweet potatoes or peeled yams in a pot with water until the vegetables turn tender. In a separate pot, combine 1 1/2 cups of chicken or turkey stock, 1/3 cup of maple syrup, the juice and zest from one orange and 4 tablespoons of butter. Season the sauce with one cinnamon stick, three or four cloves, several sprigs of thyme and 1 teaspoon of black peppercorns. Cook the sauce over medium-low heat until it's reduced. Strain the sauce into the sweet potatoes and mash the ingredients together before topping them with candied nuts.
To prepare Steve's mashed sweet potatoes with marshmallows, peel and cut 5 pounds of yams into cubes and steam them until they are tender. Blend the yams in a food-mill or food processor, adding 1 cup of dark brown sugar and 1/2 cup of butter as they mix. Stir in 1 cup of sour cream and season with 1/2 teaspoon of salt. Spoon the mixture into a casserole dish and bake it for 30 minutes at 350 degrees Fahrenheit. Sprinkle 2 cups of mini marshmallows on top, and broil for three more minutes.