Pre-heat oven to 350 degrees and grease an 8" x 8" oven-safe dish. If desired, prepare a parchment sling by cutting out a piece of parchment paper slightly larger than the pan and placing it inside.: From the moment you set the oven to 350 degrees , notice the anticipation as warmth builds and the air begins to carry the scent of baked goods. Greasing the dish ensures the edges release cleanly, and if you line with a parchment sling you will lift the bake out easily after cooling. A common error is skipping the grease or parchment, which can lead to the edges sticking and tearing when you try to slice.
In a large bowl add eggs and whisk to combine. Then almond milk, maple syrup, apple sauce, oil, and vanilla and whisk to fully combine.: As you whisk the eggs , watch the texture change from glossy to slightly frothy, this aeration helps create a light bind. Whisking fully helps distribute yolk and white evenly so the custard sets uniformly. Underwhisked eggs may cause pockets of uneven texture in the finished bake.
To the wet ingredients add oats, baking powder, chia, cinnamon, salt and grated apples and mix until fully combined.: When you add the almond milk , maple syrup , apple sauce , melted oil , and vanilla , whisk until the mixture appears homogenous, with a slightly glossy sheen. The mixture should smell faintly of maple and vanilla, indicating even distribution. If the wet mix looks separated, continue whisking, because uneven mixing can result in inconsistent sweetness and texture.
Pour into prepared 8" x 8" dish and bake for 30-35 minutes, until the center is just barely firm.: As you stir in the oats and dry ingredients, the batter will thicken and take on a speckled look from the cinnamon and chia . The grated apples will distribute and soften the batter visually, leaving little ribbons of fruit. Mix until there are no large pockets of dry oats; under mixing risks dry pockets, while overmixing can make the texture too paste like.
Scoop and serve warm as is or with almond milk, or cool and slice into 9 square portions.: When you pour the batter into the pan, spread it evenly so the top bakes uniformly and the edges crisp slightly. As it bakes the top will develop a light golden tone and the aroma of cinnamon and apple will fill the kitchen. Test the center by lightly pressing; it should be just set with a slight spring. Baking too long will dry the interior, and underbaking will leave it too gooey to slice neatly.
Scoop and serve warm as is or with almond milk, or cool and slice into 9 square portions: When the bake comes out of the oven, listen for the faint sigh as it cools, and allow it to rest so the center finishes setting. Serving warm emphasizes the tender texture and fragrant notes, while cooling allows cleaner slices into the stated 9 squares. A common misstep is slicing too soon, which can cause crumbling, so give it time to settle for the best results.