In a medium bowl, whisk together the flour, baking powder, baking soda, salt, and cinnamon.
In a separate bowl, whisk together the sourdough starter, melted butter, milk, eggs, maple syrup or honey, and vanilla until smooth.
Gently stir the dry ingredients into the wet ingredients. Mix until just combined, some small lumps are perfectly fine.
Heat a skillet over medium and melt a little butter or oil. Pour about ⅓ cup of batter per pancake.
Cook until bubbles form and the edges start to look set, then flip and cook 1 more minute or until golden.
Serve warm with butter, maple syrup, berries, yogurt, or your favorite toppings.