Spray 9-by-13-inch baking pan with vegetable pan spray.
In large saucepan, combine chicken stock, milk, salt, pepper, garlic powder and nutmeg; bring to a boil. Stir in pureed sweet potatoes; bring back to boil. While constantly whisking, add cornmeal in a slow, steady stream, making sure there are no lumps. If desired, add Orange Icing Color.
Reduce heat and continue stirring until thick, about 3 minutes. Stir in cream cheese; stir until melted and smooth. Pour into prepared baking pan. Let set at room temperature at least one hour or refrigerate for longer.
Cut into shapes with Mini Halloween Cutter Set. Serve.
Convenience tips: Leftover polenta scraps can be made into croutons. Toss with olive oil and pan fry until golden brown. Drain on paper towels. Slice premade polenta into 1/2-inch rounds and cut with Mini Halloween Cutter Set.