To a mixing bowl, add banana and mash. Then add oil, maple syrup, baking powder, and salt and whisk to combine. Then add non-dairy milk (start with the lesser amount and work your way up as needed) and whisk to combine. If using coconut oil and it hardens or clumps, it's not a big deal. You can microwave (for 45 seconds - 1 minute) to remelt - otherwise, proceed.
Add oat flour, gluten-free flour, and almond flour. Gently stir (being careful not to over-mix) to combine. It should be thick but pourable/scoopable. If too thin, add more gluten-free or almond flour. If too thick, thin with a little non-dairy milk. If adding fruit or chocolate chips, add now and gently fold to combine.
Heat a large nonstick skillet, griddle, or cast-iron skillet over medium heat. Carefully rub skillet with a little oil. (You will likely need to decrease the heat of the skillet to medium-low / low once it's hot as to not burn the pancakes.)
Once hot, spoon 1/4 - 1/3 cup of the batter onto skillet. Cook until surface of pancakes have some bubbles and the edges appear dry (~2-3 minutes). Carefully flip pancakes and cook until browned on the underside (~3 minutes more). The gluten-free flour blend benefits from a slightly longer cooking time, so don’t be shy to get a nice golden brown color on both sides.
Transfer cooked pancakes to a baking sheet or plate (don’t stack pancakes on top of one another) and keep warm in a 200-degree F (94 C) oven. Continue cooking until all batter is used up - about 12 pancakes (as original recipe is written).
These pancakes are delicious on their own, but they're amplified with toppings such as additional fruit or chocolate chips, peanut butter, and maple syrup.
Store cooled leftover pancakes (without toppings) in a container separated with wax or parchment paper to prevent sticking. Will keep in the refrigerator up to 4 days or in the freezer* up to 1 month. Reheat in the toaster oven, microwave, or oven until hot.
*To freeze pancakes, add cooled pancakes to a Tupperware or plastic bag with parchment or wax paper in between to prevent sticking. Reheat in a toaster oven, oven, or microwave until hot and fluffy. I prefer to heat in the toaster and then microwave for 15-20 seconds to make fluffier and softer. *Nutrition information is a rough estimate calculated with almond milk and without optional ingredients.