makes one 9-inch cake
2 cups flour
1/2 cup sugar, plus extra for sprinkling
2 teaspoons baking powder
1/4 teaspoon baking soda
1/4 teaspoon sea salt
6 tablespoons cold butter, cut into 24 pieces
1 1/4 cup buttermilk
2 peaches, diced
3/4 cup fresh blueberries
Preheat oven to 400ºF. Grease a 9-inch glass or ceramic pie plate.
Whisk the flour, 1/2 cup sugar, baking powder, baking soda and salt together in a medium bowl. Add the butter and rub together wuickly with fingertips until small, pea-size pieces form. Pour in the buttermilk and stir until it just comes together to form a batter. Fold in the peaches and blueberries.
Scrape the batter into the prepared pie plate and smooth top into an even layer using a rubber spatula. Sprinkle top with extra sugar, if desired. Bake for 35 to 37 minutes.