Preheat oven to 350°F.

Melt butter in 10" cast iron skillet; set aside.

Whisk flour, salt, cinnamon, baking soda and baking powder in a small bowl.

Whisk molasses, egg, ginger and 1/4 cup of sugar in a large bowl. Whisk in sour cream then the milk. Gragually whisk in the dry ingredients, then 3 tablespoons of the melted butter. Set aside.

Peel and core apples. Cut apples into 3 triangular pieces. Over medium heat, add remaining sugar to butter in the skillet. Heat until sugar becomes caramelized. Add apples round side down and stir to coat. Cook for about 3 minutes. Turn apples over and cook until they begin to soften, about 5 minutes longer. Arrange apples evenly in skillet flat side down. Pour batter over apples. Bake 30-40 minutes until done.

Allow cake to cool about 10 minutes then invert onto plate. Serve warm or at room temperature.