Mix flour, sugar and cinnamon. Cut butter into the flour mixture until small crumbs form.
Arrange apple slices in a circular pattern on the baking dish. (I would us an 8x8 one.) Sprinkle with lemon juice.
Cover apples evenly with flour mixture. (I would press lightly.) Bake at 350F for 35-45 minutes.
After it has cooled, invert onto a platter and sprinkle with a little powdered sugar.
VARIATION: Place baking dish on stove top with 1/2 cup sugar and a little butter. Cook until sugar becomes brown and caramelized. Then the apples are placed in it as described above, with the crumbs on top, and then baked. Makes for a nice caramelized look.