Blackberry Cobbler

INGREDIENTS
1/2 cup (1 stick) unsalted butter
4 cups fresh blackberries
1 cup sugar, plus more for sprinkling
1 cup all-purpose flour
2 teaspoons baking powder
Pinch of fine sea salt
1 cup whole milk
1 teaspoon pure vanilla extract
Whipped cream or ice cream, for serving

DIRECTIONS
1. Preheat oven to 350 degrees.

2. Melt butter in a large cast-iron skillet or ovenproof baking dish, in the oven, 5 to 7 minutes.

3. Meanwhile, place blackberries in a large bowl. Using a potato masher, mash blackberries to release their juices. If blackberries are tart, sprinkle with sugar.

4. In another large bowl, whisk together flour, baking powder, and salt. Add 1 cup sugar, milk, and vanilla extract; mix until well combined. Remove skillet from oven and add melted butter to flour mixture; stir to combine. Pour mixture into skillet and pour blackberries and their juices into the center.

5. Transfer skillet to oven and bake until top is golden brown and a cake tester inserted into the batter comes out clean, about 1 hour. Serve hot, warm, or at room temperature with whipped cream, creme fraiche, or ice cream.