Preheat oven to 350°F and line a 9" x 5" loaf pan with parchment. Instead of parchment paper, lightly oil the loaf pan with cooking spray.
Remove core and cut apple into small pieces. Shred apples with a box grater instead of chunks.
Blend oats for 30 seconds in a high-powered blender to make flour. Blend baking powder, sea salt, and ground cinnamon for a few seconds to combine all the dry ingredients. Hold until use.
Applesauce, eggs, avocado oil, pure maple syrup, and vanilla extract should be mixed in a large bowl.
Mix dry and wet ingredients until a thick batter forms. Evenly distribute chopped apples into batter.
Evenly distribute apple bread batter in pan. Additional oats can be added to the batter for appearance.
Cook the loaf pan under foil for 40 minutes on the centre rack of the preheated oven. Without foil, bake the bread for 20–30 minutes until clean and slightly golden brown.
Quick breads finish at 190–200°F. To check bread doneness, insert a digital thermometer into the centre for best results. Once room temperature, slice and serve the bread.