Bring the wine, sugar, cinnamon stick, cloves, allspice and peppercorns to a simmer in a saucepan over medium heat, stirring until the sugar dissolves. Cook 5 minutes, then remove from the heat and let stand 15 minutes. Strain the mulled wine into an 8-inch-square baking dish and freeze until hard, about 5 hours. Scrape with a fork and divide among glasses. Serve with whipped cream.