Preheat your oven to 350°F (175°C) and lightly grease a small oven-safe baking dish with a touch of coconut oil or avocado oil spray.
Core and dice the Fuji apple into small, bite-sized pieces.
In a medium mixing bowl, whisk together the liquid egg whites, unsweetened almond milk, vanilla extract, ground cinnamon, and sea salt until well combined.
Stir in the rolled oats, hemp seeds, and approximately two-thirds of the diced apples.
Pour the oat mixture into the prepared baking dish and scatter the remaining apple pieces evenly over the top.
Bake for 25 to 30 minutes, or until the oats are set in the center and the edges are slightly golden brown.
While the oats bake, prepare the sauce by whisking the plain nonfat Greek yogurt and pure maple syrup together in a small bowl until smooth.
Remove the oats from the oven and let them cool for about 5 minutes to firm up.
Drizzle the maple-yogurt sauce over the warm baked oats and serve immediately.