Ingredients:
For the Apple Filling:
4 to 5 medium apples (peeled, cored, and chopped)
2 tablespoons butter
1/2 cup brown sugar
1 teaspoon ground cinnamon
1 tablespoon lemon juice (optional)
1 tablespoon cornstarch (for thickness, optional)
For the Cake Batter:
1 and 1/2 cups all-purpose flour
1/2 cup unsalted butter (softened)
1/2 cup granulated sugar
2 large eggs
1/2 cup milk (or yogurt)
1 teaspoon vanilla extract
1 and 1/2 teaspoons baking powder
1/2 teaspoon ground cinnamon
1/4 teaspoon salt