Mash the bananas. In a large bowl, mash the bananas with a fork until mostly smooth with a few small lumps. You should have about 3/4 to 1 cup of mashed banana.
Whisk the wet ingredients. Add the egg, milk, vanilla, and melted butter to the mashed bananas.
Whisk until well combined.
Combine the dry ingredients. In a separate bowl, mix the flour, sugar, baking powder, cinnamon, and salt. Stir to evenly distribute the leavening and spices.
Bring the batter together. Add the dry ingredients to the wet and gently stir until just combined. A few streaks of flour are okay.
If using add-ins, fold them in now. The batter should be thick but pourable—add a splash more milk if needed.
Preheat the pan. Heat a nonstick skillet or griddle over medium heat. Lightly grease with butter or oil.
The surface is ready when a drop of water sizzles and evaporates quickly.
Cook the pancakes. Scoop 1/4 cup of batter for each pancake. Cook until bubbles form on the surface and the edges look set, about 2–3 minutes. Flip and cook the other side for 1–2 minutes, until golden and cooked through.
Adjust heat as needed. If pancakes brown too quickly, lower the heat.
Every stove runs differently, so aim for steady, gentle heat.
Serve warm. Top with butter, maple syrup, sliced bananas, yogurt, or peanut butter. A sprinkle of chopped nuts adds crunch.