Ingredients

For topping

3 tablespoons unsalted butter

　　1/2 cup packed light brown sugar

　　1 lb Granny Smith apples, peeled, cored, and cut into thin wedges

　　

For biscuit cake

1 cup all-purpose flour

　　1/4 cup granulated sugar

　　1 teaspoon baking powder

　　1/2 teaspoon baking soda

　　1/2 teaspoon salt

　　1/2 teaspoon cinnamon

　　5 tablespoons cold unsalted butter, cut into pieces

　　1/2 cup well-shaken buttermilk

　　Accompaniment: crème fraîche or sour cream (optional)

　　

Step 1

Preheat oven to 425°F.

　　

Make topping:

Step 2

Heat butter in an ovenproof 10-inch heavy skillet (preferably well-seasoned cast-iron) over moderate heat until foam subsides. Stir in brown sugar and remove from heat. Spread mixture evenly in skillet and arrange apples, overlapping, in 1 layer.

　　

Make cake:

Step 3

Blend flour, sugar, baking powder and soda, salt, and cinnamon in a food processor. Add butter and pulse until mixture resembles coarse meal. Transfer to a bowl and add buttermilk, stirring just until mixture is moistened.

　　

Step 4

Drop batter on top of apples and gently spread, leaving a 1-inch border around edge of skillet. (Cake needs room to expand.)

　　

Step 5

Bake cake in middle of oven until golden brown and firm to the touch, 25 to 30 minutes. Cool cake in skillet on a rack 3 minutes, then invert onto a platter. Replace any apples that stick to skillet on cake.

　　

Step 6

Serve warm.