Preheat oven to 350 degrees Farenheit. Grease a 9 x 9 pan or pie plate.
In a big bowl, crack and whisk eggs.
Add brown sugar and mix well.
Add baking powder, vanilla, salt, and cinnamon and mix again.
Add melted butter and milk and stir.
Stir in oats and flax.
Mix in the diced apples.
Pour into your greased pan.
Bake for 30 minutes. Let cool and enjoy!