Step 1: Preheat the oven to 350°F (175°C).
Step 2: In a large mixing bowl, mash the ripe bananas with a fork until smooth. Add in the almond milk, maple syrup, almond butter, and vanilla extract. Mix until well combined.
Step 3: Sprinkle in the oats, baking powder, and cinnamon. Stir until everything is well incorporated.
Step 4: Gently fold in the raspberries, being careful not to crush them too much.
Step 5: Pour the mixture into the prepared baking dish and spread it out evenly with a spatula.
Step 6: Bake for 30-35 minutes or until the top is golden brown and a toothpick inserted in the center comes out clean.
Step 7: Allow to cool for about 10 minutes, cut into squares, and serve warm.