Measure out the flour, baking powder, baking soda and salt into a large bowl.
In a separate bowl, mash the bananas very well (it's ok if they go a little bit liquidy...you don't want any large chunks). Add the eggs and the vanilla and beat with a fork until they're combined well.
Measure the buttermilk into a separate liquid measuring cup and pour the buttermilk and the egg mixture into the flour mixture.
Stir everything together carefully, making sure you don't over mix, until everything is combined.
Heat a large non-stick skillet or griddle over medium heat.
Let the batter sit in the bowl for about 5-6 minutes before you start frying. This will allow the leavening agents (the baking powder and baking soda) time to begin their work and you'll start to see the batter start to rise slightly as air bubbles develop below the surface.
Once the oil has heated for a few seconds, turn the heat down to medium-low heat and carefully ladle about 1/3 cup of batter into the pan for each pancake, trying to disturb the batter as little as possible. This will help the air bubbles stay intact as the pancake cooks and create a light and fluffy texture. This is especially important when using whole wheat flour because the wheat particles in the flour actually interfere with gluten development, making baked goods made with whole wheat flour denser and generally less fluffy than their all-purpose flour counterparts.
Once you see the edges beginning to brown slightly and a few bubbles breaking the surface of the batter, flip the pancakes over. You can check the underside by lifting up the edge of one of the pancakes using a spatula; if the underside is brown, it's time to flip!
Repeat this process until all your batter is gone. The number of pancakes you make will vary based on the size you choose and the pan you're using, but this recipe feeds our family of four with several pancakes left over for the next day (usually around a total of 12-16 pancakes).
Serve the pancakes hot off the griddle with some fresh berries and maple syrup!