Preheat the oven to 350 degrees. Cover a baking sheet with foil.
In a medium sauce pan over low heat mix together all ingredients, except the sweet potatoes. Stir until the sauce is smooth and heated through. Remove from heat.
Toss in the sweet potatoes and cover thoroughly with the glaze.
Pour out the sweet potatoes and glaze onto the foil covered baking pan. Cover the pan with foil.
Bake for 20 minutes
Remove the foil and increase the temperature to 400 degrees and cook for 10 minutes.