Mix first 4 ingredients together in a large bowl and set aside.
In a medium bowl, mash banana with a fork or potato masher.
Add in walnut oil, milk, vanilla and beaten egg yolks.
Mix ingredients to combine.
Add wet ingredients to dry ingredients.
In a separate bowl beat the 1 egg white until frothy and a stiff peak forms.
Fold egg white into the pancake batter several times until incorporated.
Heat a cast iron skillet sprayed with cooking spray. (I like using coconut spray from Trader Joe's)
Using a ladle, pour pancake batter onto skillet and let cook for about 3-4 min. (Or until bubbles form. Check for doneness with a pancake flipper when pancake is a golden brown.)
Flip over and cook for another 2 min.
Recipe by Sweet Is The Spice at https://sweetisthespice.com/recipes/breakfast/pancakes/banana-pancakes/