Preheat oven to 375°F and grease or line an 8x8 baking dish.
In a large bowl, whisk together oats, cinnamon, baking soda, baking powder, flaxseed, and salt.
In another bowl, whisk together yogurt, eggs, applesauce, maple syrup, vanilla, almond extract, and milk.
Pour wet ingredients into dry ingredients and stir well. Let the mixture sit for 10 minutes so the oats can absorb some liquid.
Stir in 1¾ cups of the berries, reserving the remaining ¼ cup for the top.
Pour mixture into the prepared baking dish. Scatter remaining berries and slivered almonds on top. Bake for 35–40 minutes, until set and lightly golden.
Let cool slightly before slicing. Serve warm or chilled, optionally topped with extra yogurt