3 tablespoons unsalted butter, cut into 1/2-inch dice
6 cups pitted sour cherries
1 teaspoon grated orange zest
1/4 teaspoon ground star anise (optional)
1 1/2 tablespoons crystallized sugar or crushed sugar cubes
In a medium bowl, whisk the buttermilk with the polenta and vanilla and set aside for 30 minutes.
Preheat the oven to 400°. In a large bowl, combine the flour, 6 tablespoons of the granulated sugar, the baking powder and the salt. Cut or rub in the butter until the mixture resembles coarse meal. Slowly stir in the buttermilk mixture to form a loose wet dough; do not overmix.
In a shallow 1 1/2- to 2-quart baking dish, toss the cherries with the orange zest, star anise and the remaining 1 cup of granulated sugar. Drop spoonfuls of the topping over the cherries and sprinkle with the crystallized sugar. Set the dish on a baking sheet and bake for about 45 minutes, or until the topping is golden.