Combine the almond milk and vinegar and let sit. Whisk together all dry ingredients. Gently stir in the almond milk mixture, olive oil and vanilla until a lumpy batter forms. You can add additional water or milk at this point for thinner pancakes (I prefer thick ones).
Lightly grease a medium frying pan over medium heat. Drop a heaping tablespoon of batter into the preheated pan (batter should sizzle), then press a couple slices of banana in the center. Dollop a heaping quarter teaspoon of nut butter, jam, or both on top of the banana, then top with another banana slice, and then enough batter to just cover the filling. Let cook until you can easily slide a spatula underneath the pancake (about 2 minutes), then flip and cook until the other side is browned. Serve hot! Leftovers taste best reheated on the stovetop.