Combine the oats and milk in a bowl and let them sit for about 10 minutes so the oats soften. This gives the pancakes a better texture.
In another bowl, whisk together the flour, brown sugar, baking powder, salt, and cinnamon.
Add the eggs, melted butter, and vanilla to the oat mixture and stir until smooth.
Gradually fold the dry ingredients into the wet mixture, mixing just until combined. Don’t overmix. That's what keeps them light.
Heat a nonstick pan or griddle over medium heat and lightly grease it with butter.
Pour about ¼ cup of batter into each pancake. When bubbles appear on the surface, flip the lid and cook until golden brown on both sides.
Keep the cooked pancakes warm under foil while you finish the rest.
