Preheat the oven to 350°F (180°C). Line an 8-inch baking pan with parchment paper. Lightly oil with cooking oil spray. Set aside.
In a mixing bowl, stir almond flour, quick oats, oat flour, almond milk, maple syrup, and almond extract until smooth. It won't be too thick, a bit liquid, that's normal.
Pour into the prepared pan. Meanwhile, make the topping.
In a small bowl, stir all the almond paste ingredients until they form a thick paste that resembles marzipan. If too dry, add some almond milk. It should be thick like a paste but not crumbly.
Drop dollops of the paste all over the pan and press to spread roughly all over the pan and create a second layer on top. It won't cover all the first batter layer, that's fine.
Sprinkle the sliced almonds all over the top and press a little so they stick to the batter.
Bake the bars on the center rack of the oven for 40 minutes at 350°F (180°C) until the top is set, golden, and a toothpick inserted in the center of the bars comes out clean.
Let the bars cool down for 10 minutes in the pan at room temperature, then cool down for 1 hour on a cooling rack before slicing.
Slice into 9 bars and serve as a breakfast with a drizzle of maple syrup and a dollop of yogurt. Dust with powdered sugar just before serving.
