Toss together the sliced apples and lemon juice, set aside. In a small bowl mix together cinnamon and sugar, set aside.
Cream the butter and sugar, then add the eggs one at a time, beat well to combine, then add the oil, vanilla and milk, beat until smooth.
Mix flour, baking powder and 1 teaspoon cinnamon, add to batter and beat on medium until smooth.
Spoon batter into the prepared cake pan, top with sliced apples (do not press down), sprinkle with the cinnamon sugar mix. Bake.