In a large bowl, combine the oats, flour, brown sugar, baking soda, baking powder, salt, and cinnamon. Whisk in the eggs, buttermilk, and vanilla and mix well.
Spray a griddle or skillet with cooking spray and cook over medium heat. Cook pancakes until bubbles appear on the top layer, about 5 minutes. Flip and cook until evenly browned, about 3 more minutes.
Serve with butter and maple syrup.