Preheat Your Oven: Preheat your oven to 350°F (175°C). Line an 8×8-inch baking pan with parchment paper or lightly grease it.
Prepare Flax Eggs: In a small bowl, mix 2 tablespoons of flaxseed meal with 5 tablespoons of water. Let it sit for 5-10 minutes to thicken.
Mix Wet Ingredients: In a large mixing bowl, mash the ripe bananas until smooth. Add the unsweetened applesauce, almond milk, vanilla extract, and prepared flax eggs. Stir until well combined.
Combine Dry Ingredients: In another bowl, whisk together the True Nutrition Banana Smoothie Pea Protein, almond flour, baking powder, baking soda, cinnamon (if using), and a pinch of salt.
Mix Wet and Dry Ingredients: Gradually fold the dry ingredients into the wet ingredients until well combined. Be careful not to overmix.
Add Walnuts: Gently fold in the chopped walnuts for a nice crunch in every bite.
Bake: Pour the batter into the prepared baking pan, spreading it out evenly. Optional: top the bars with extra walnuts and sliced banana before baking. Bake for 25-30 minutes or until a toothpick inserted in the center comes out clean.
Cool and Slice: Allow the cake bars to cool completely in the pan before cutting them into squares. Frost with homemade cream cheese frosting if desired!