In a medium bowl, add flour, sugar, baking powder, salt, and cinnamon, and stir until well combined.
In a large bowl, add milk, egg, melted butter, and vanilla extract, and whisk until well combined. Add the dry mixture to the wet mixture and mix gently to combine. Add diced apple and gently fold into the mixture – be careful not to over mix the batter.
Heat a griddle or pan to medium heat, add a knob of butter, and allow to melt. Working in batches, add a 1/4 cup of the batter to the griddle or pan and cook until bubbling on top, flip and cook for an additional 1-2 minutes per side until golden brown.
Continue this process until all of the batter is done. You can store the cooked pancakes in the oven at 200°F to keep them warm.
Optional: While the pancakes are cooking, prepare the topping. In a small pan or saucepan, add butter, diced apples, and cinnamon, and cook on medium heat for 3-5 minutes until apples are tender. Once tender, add maple syrup, stir to combine, and allow to cook for an additional 1-2 minutes. If the mixture gets too “sticky” simply add a splash of water to loosen it up.
Once complete, serve pancakes with apple topping and/or additional maple syrup.