Heat a large non-stick pan over medium-high heat. Once hot, melt the butter. Add the chopped apples to the pan, and stir, cooking them for about a minute.
Distribute the cinnamon and brown sugar over the apples, give them a stir, and add the water. Cook the apple topping for 5 minutes, until the apples have softened enough to your liking. Turn off the heat and set aside.
Make the pancake batter:
Place all the ingredients in the blender in the order listed, making sure the milk is first so the ingredients blend more easily. Blend for 1 minute, until it's smooth and thick. Pour the batter into a large bowl, using a spatula to scrape the sides of the blender to get it all in.
Gently fold the cinnamon apples into the batter with a spatula until they're evenly distributed throughout the batter. Let this sit in the bowl for 5 minutes to help the oats absorb the moisture. The batter will be thick.
Cook the pancakes:
Heat a large non-stick pan (or griddle) over medium-high heat. Once hot, grease the surface with oil, spray, or butter. Immediately, pour ¼ cup of pancake batter onto the greased pan, making sure each pancake has some of the apples.
Cook the pancakes for about 2 minutes, until the edges begin to look defined and bubbles form. Flip the oat pancakes over and cook for another minute on the other side. Make sure not to press them down with the spatula. Remove from the pan, keep the pancakes warm, and repeat with the rest of the pancake batter.
Serve:
Serve these apple oatmeal pancakes with a little butter, maple syrup, or your favorite toppings.
Notes
Use the right baking powder: Since pancake batter naturally has a mild, neutral flavor, it's important to use aluminum-free baking powder. The metallic flavor will ruin the taste, especially in fluffy pancake recipes that call for 2 or more teaspoons. Trust me on this one.