Mix all dry ingredients: flour, oats, baking soda, baking powder, salt, and cinnamon. Put it aside.
Add banana yogurt, coconut oil, and eggs. You welcome to use plain yogurt. If you using small egg like me, add 2 eggs and 1 egg yolk. Mix everything well.
Add in sugar in the bowl and mix it well. Since I used really ripe banana, I okay use half cup of brown sugar.
Pour all the dry ingredients into the mixture and mix everything well.
Add crushed walnuts.
Pour into baking pan. Bake at 350F for 40-50 min.
Wait until it cool down( around 10min) and slice it. Enjoy 😋