Place peeled bananas in a large mixing bowl. Mash with a fork.
Add melted butter, buttermilk, eggs and vanilla. Whisk together well.
Add remaining dry ingredients and whisk until all white streaks of flour have disappeared. If a few lumps remain, that's okay.
Heat a well seasoned, 12 inch cast iron skillet to medium low. Add approximately 2 teaspoons cooking oil. Test for the correct heat with a few drops off water. They should bounce and sizzle.
Add 1/4 cup batter to hot skillet. In a 12 inch skillet, there's room for three pancakes at the time.
Cook on one side for 2 to 3 minutes or until bubbles start to form on the top. Flip over and cook for an additional minute or two until the pancake is done. Remove.
Repeat with remaining batter.
Serve warm with butter and syrup.