gingerbread apple upside-down cake

INGREDIENTS

• 4 tablespoons butter, plus extra for greasing pan
• 1/2 cup dark brown sugar
• Pinch of salt
• 4 apples (about 1 3/4 pounds), peeled, cored and cut into 1/4-inch wedges
• 1/2 cup (1 stick or 4 ounces) butter, at room temperature
• 1/2 cup sugar
• 1 large egg
• 1/3 cup dark molasses
• 1/3 cup honey
• 1 cup buttermilk
• 2 1/4 cups flour
• 1 teaspoon baking soda
• 1/2 teaspoon salt
• 1 teaspoon ground ginger
• 1 teaspoon cinnamon