If baking right away, preheat oven to 350 degrees.
Grease a 9x13 baking dish and set aside.
In a large bowl, whisk together the rolled oats, brown sugar, cinnamon, baking soda, and salt.
In a medium bowl, whisk together the eggs and milk. Slowly whisk in the melted butter.
Mix the wet ingredients into the dry ingredients until just combined.
Fold in the chopped apples.
Pour the oatmeal mixture into the prepared baking dish.
Bake at 350 degrees for 20-22 minutes.
This recipe may be prepared the night before, refrigerated, and baked in the morning. It reheats well as leftovers. It can also be frozen (before baking) for up to 3 months. Defrost and bake as directed.