Heat your oven to 350 degrees. Spray a large pie plate or baking dish with cooking spray. Set aside.
In a medium saucepan, combine the cranberries, water, 1/4 cup sugar, and cinnamon. Heat over medium-low heat, stirring constantly. Continue heating until the cranberries begin to burst and the sauce thickens, about 5 minutes. Stir in the pomegranate seeds. Set aside.
In a large mixing bowl, whisk together the flour and 1 cup of sugar. Add in the buttermilk and continue whisking. Then pour in the melted butter and whisk until well combined. Pour the batter into the prepared baking dish. Spoon the cranberry-pomegranate mixture evenly over the top of the batter. Then sprinkle the chocolate chunks or chips evenly over the batter.
Bake at 350 for about 1 hour, or until bubbly and golden brown. Sprinkle with sparkling sugar, if desired. Allow to cool to warm and then serve with whipped cream or vanilla ice cream.