Preheat oven to 350°F (177°C). Line an 8 inch by 8 inch baking pan with parchment paper leaving some overhang for easy removal later.

If you are using store bought applesauce, you can skip steps 2-3. Add the 360 grams of large cubed apples into a pot filled with water. Bring to a simmer on the stove and cook the apples until they are fork tender. Drain and remove the cooked apples from the water and place into a blender.

Blend the apples for a few seconds until they reach an applesauce consistency. Your applesauce should be thick, grainy-like consistency but without visible chunks of apples. If you still have apple chunks, you won't have enough liquid for your oat mixture. You should have 1.5 cups of applesauce.

Add the applesauce to a large mixing bowl. Add in the maple syrup and apple pie spice and mix until evenly combined.

Add in the quick oats and mix with a spatula until the oats are fully incorporated. Your mixture should be thick. Taste, and if needed, you can add a little more maple syrup or apple pie spice.

Stir in the small apple cubes until they are evenly mixed in.

Transfer the batter into your prepared baking pan. Use a spatula to evenly spread it across the pan and smooth the surface.

Bake for about 35-40 minutes or until the bars are lightly golden on the surface and cooked through.

Let bars cool fully before removing them from the pan and cutting and serving. Store uneaten bars in an airtight container in the fridge or freezer.