Preheat the oven to 350 degrees F. Lightly grease 2 standard 12-cup muffin tins with baking spray.
In a large bowl, whisk together the eggs, milk, cashew butter, bananas, maple syrup, and vanilla extract.
Stir in the rolled oats, baking powder, salt, and cinnamon until the ingredients are evenly combined.
Divide the mixture between the two muffin tins. The cups won't rise much in the oven, so you can fill the tins almost all the way to the top (leave room for the topping).
Top each oatmeal cup with chopped nuts and dried fruit, gently pressing down to help them adhere during the cooking process.
Bake for 20-23 minutes, until a toothpick comes out clean. Allow to cool for 5 minutes before transferring to a cooling rack. The oatmeal cups will keep in the refrigerator for 5 days, or you can wrap them individually and store in the freezer.