6 tablespoons unsalted butter, softened, plus more for pie plate
1 1/2 cups all-purpose flour
1 1/2 teaspoons baking powder
1/2 teaspoon salt
1 cup plus 2 tablespoons sugar
1 large egg
1/2 cup milk
1 teaspoon pure vanilla extract
1 pound strawberries, hulled and halved
Preheat oven to 350 degrees. Butter a 10-inch pie plate. Sift flour, baking powder, and salt together into a medium bowl.
Put butter and 1 cup sugar in the bowl of an electric mixer fitted with the paddle attachment. Mix on medium-high speed until pale and fluffy, about 3 minutes. Reduce speed to medium-low; mix in egg, milk, and vanilla.
Reduce speed to low; gradually mix in flour mixture. Transfer batter to buttered pie plate. Arrange strawberries on top of batter, cut sides down and as close together as possible. Sprinkle remaining 2 tablespoons sugar over berries.
Bake cake 10 minutes. Reduce oven temperature to 325 degrees. Bake until cake is golden brown and firm to the touch, about 1 hour. Let cool in pie plate on a wire rack. Cut into wedges.