In a medium mixing bowl, combine the oats, walnuts, cinnamon, baking powder, salt and nutmeg.
Whisk to combine.
In a smaller mixing bowl, combine the milk, maple syrup, egg, half of the coconut oil, and vanilla.
Whisk until blended.
Spiralize the apple with Blade C.
Reserve half of the apple for topping the baked oatmeal, then arrange the remaining apples evenly over the bottom of the baking dish.
Cover the apples with the dry oat mixture, then drizzle the wet ingredients over the oats.
Wiggle the baking dish to make sure the almond milk moves down through the oats, then gently pat down any dry oats resting on top.
Scatter the remaining apple noodles on the top.
Bake for 35 to 45 minutes, until the top is nice and golden.
If any of the apple noodles start to burn, tuck them into the oatmeal or snip them.
Remove your baked oatmeal from the oven and let it cool for a few minutes.
Drizzle the remaining coconut oil on the top before serving.
Will this turn into a soggy porridge once it cools down on the counter? Initial tests of baked grain dishes frequently yield a gummy middle that refuses to slice cleanly into portions. Structure relies entirely on hydration management and precise baking times. Whisking the almond milk, eggs, maple syrup, and melted coconut oil thoroughly before adding them to the dry old-fashioned oats prevents dry pockets from forming in the corners of a nine-inch baking dish. Wiggling the vessel forces the liquid down through the oats so every grain absorbs moisture evenly without drowning. Baking at 375 degrees for thirty-five to forty-five minutes creates a golden crust on top while setting the center properly. If the spiralized Honeycrisp apple noodles on the surface darken too quickly, tuck them into the surrounding oat mixture immediately to prevent acrid bitterness.
Leftovers demand a specific reheating strategy to recover that lost texture. Chilled portions straight from the refrigerator lose their integrity, turning dense and heavy. Slicing the cold block into individual squares and crisping them in a hot skillet with a thin film of neutral oil reactivates the toasted walnuts and firms the interior.
Dietary adaptations require minimal structural changes. Substituting the dairy-free almond milk with standard cow milk alters neither the chemical leavening power of the baking powder nor the binding capacity of the two large eggs.