Preheat your oven to 350°F (175°C). Line an 8x8-inch baking dish with parchment paper, making sure to leave some overhang for easy removal. Spray the lined dish with nonstick cooking spray to prevent sticking.

In a small bowl, combine the rolled oats, baking powder, and salt. Whisk these together thoroughly to ensure the leavening and seasoning are distributed evenly throughout the oats.

In a large mixing bowl, whisk together the milk, maple syrup, unsweetened applesauce, freshly squeezed lemon juice, eggs (make sure they're at room temperature for best results), olive oil, grated lemon zest, and almond extract until well blended.

Add the oat mixture from Step 2 to the bowl with the wet ingredients from Step 3. Stir until everything is just combined and the oats are evenly moistened with no dry patches remaining.

Gently fold in the fresh blueberries with a rubber spatula, being careful not to break them. If you want an extra burst of fruit, I like to sprinkle a handful of extra blueberries over the top right before baking for a pretty, fruity finish.

Pour the oatmeal mixture from Step 5 into the prepared baking dish from Step 1. Spread it evenly with a spatula. Bake in the preheated oven for 45–55 minutes, until the edges are golden brown and the center feels set and firm.

Remove the baked oatmeal from the oven and let it cool in the pan for 45–60 minutes. Slice and serve, optionally topped with Greek yogurt, extra blueberries, lemon zest, and a drizzle of honey or maple syrup if desired. I find letting it cool completely makes the squares hold together much better.