Preheat the oven to 350 degrees Fahrenheit, and line a muffin pan with muffin papers (if you prefer going without muffin papers, you can spray the muffin holes with cooking spray).
Mash the bananas in a large bowl until most of the chunks are out.
Stir in the almond butter (or nut/seed butter of choice) until creamy.
Add in the eggs and non-dairy milk and stir well until all of the wet ingredients are combined.
Transfer the dry ingredients (oats, ground cinnamon, and sea salt) to the mixing bowl and stir until well combined.
Stir in the blueberries.
Fill the muffin holes with the oatmeal mixture, filling the holes most of the way up. If you’d like, you can top the batter with more fresh blueberries.
Bake on the center rack of the preheated oven for 30 to 35 minutes, or until the oatmeal cups appear set up and golden-brown.
Allow the oatmeal cups to cool completely before serving. This ensures the muffin papers don’t stick to the oatmeal, as they will if they are still hot when served.
If you’d like, serve the baked oatmeal with additional fresh fruit, yogurt, butter, and honey or a drizzle of pure maple syrup.