Prep the Oven and Skillet: Preheat your oven to 350°F (175°C). Place a 10-inch cast iron skillet in the oven while it heats up to warm the skillet.
Prepare the Fruit Mixture: In a mixing bowl, combine the blueberries, sliced peaches, 1/4 cup of granulated sugar, vanilla extract, and ground cinnamon. Toss gently until the fruits are evenly coated. Set aside.
Make the Cobbler Batter: In a separate bowl, whisk together the flour, baking powder, salt, and remaining 1/4 cup of granulated sugar. In another bowl, mix the melted butter, milk, and lemon juice until combined. Pour the wet ingredients into the dry and stir until just combined; do not overmix.
Combine and Cook: Remove the hot skillet from the oven. Pour the fruit mixture into the skillet evenly. Spoon the cobbler batter over the fruit, allowing it to spread naturally for a rustic look.
Bake: Place the skillet back in the oven and bake for 30-35 minutes, or until the top is golden brown and a toothpick inserted into the center comes out clean.
Cool and Serve: Once done, remove it from the oven and let it cool for a few minutes. Serve warm in the skillet, optionally topped with a scoop of vanilla ice cream.
Notes
Serve directly from the skillet for a rustic feel. Garnish with powdered sugar and fresh mint leaves.