In a large mixing bowl, thoroughly mash bananas. Whisk in eggs one at a time. Stir in melted coconut oil.
Add flours, baking powder and milk until mixture is pourable. Stir in vanilla and lemon zest.
Spray non-stick spray over a griddle or non-stick skillet heated over medium-low heat. Add pancakes in 1/4 cup at a time. Cook until bubbles appear on top and the pancakes are golden on the bottom, about 4 minutes. Flip and cook until golden on the other side, about 2 more minutes.