In a large mixing bowl, whisk together the whole wheat flour, baking powder, and salt until evenly combined.
Peel and mash the bananas with a fork until smooth, then add them to the bowl.
Pour in the milk and add the eggs, then whisk everything together until the batter is just combined. It will be slightly lumpy but well incorporated.
Stir in the oil and vanilla extract if using, mixing gently to incorporate.
Preheat your griddle or non-stick skillet over medium heat until hot, and lightly grease with additional oil or butter to prevent sticking.
Pour about 1/4 cup of batter onto the hot skillet for each pancake, settling it into a round shape.
Wait until bubbles form on the surface and the edges look set, about 2-3 minutes, then gently flip the pancakes with a spatula.
Cook for another 2-3 minutes on the second side until golden brown and cooked through.
Remove the pancakes from the skillet and keep warm while you repeat with the remaining batter.
Serve warm, topped with additional bananas, syrup, or your favorite toppings.