In a large mixing bowl, add the flour, salt, sugar, baking powder, baking soda and cinnamon. Whisk together. Create a hole in the center of the flour mixture to add your wet ingredients.
Add the egg to the center of the flour mixture. Whisk the eggs to break the yolks, being careful not to incorporate the flour yet. Add in the buttermilk, vanilla extract, cooled melted butter, and grated zucchini into the center of the flour. Gently combine the wet and dry ingredients together, being careful not to overmix. Let the batter rest while you make the cinnamon sugar butter.
For the cinnamon sugar butter, combine the melted butter, cinnamon and brown sugar together in a bowl. Stir until fully combined. Add the cinnamon sugar butter mixture to a piping bag or zip lock bag. You can also skip the bag, and just spoon the cinnamon butter onto the batter.
Heat a large griddle or skillet greased with butter to medium heat. Add a ladle of pancake batter (you can make 8-10 small pancakes or 4-5 large pancakes) to the heated griddle.
If using a piping bag or zip lock bag, cut off one corner of the bag. Gently add a spiral of cinnamon butter over each pancake. You can also carefully spoon the cinnamon over the pancakes.
Cook the pancakes until the edges are set and the bottom of the pancake is golden brown. Flip and cook the other side of the pancake is brown. Repeat until all batter has been cooked.
Enjoy the pancakes with maple syrup, whipped cream or a cream cheese glaze.