Mashed Sweet Potatoes with Truffles and Bourbon

8 medium (4 pounds) sweet potatoes
1/4 cup butter, melted
1 small black truffle, chopped (optional)
2 to 3 teaspoons black or white truffle oil
2 tablespoons light corn syrup
1/2 teaspoon salt
1/4 cup bourbon whiskey

Heat oven to 350 degrees F. Bake the sweet potatoes for approximately 60 to 90 minutes or until tender; remove from oven. Peel and mash the sweet potatoes with a potato masher or ricer (do not use your electric mixer) until they're smooth and free of chunks. Add melted butter, optional chopped truffle, corn syrup, salt, and bourbon. Mix thoroughly to blend. Pour into a baking dish and bake for approximately 30 minutes or until warmed through. Makes 6 to 8 servings.