Preheat the oven to 350 degrees.
Grease 9 x 9 inch baking pan.
Combine oats, flour, salt, baking powder and cinnamon into a mixing bowl, and stir.
Mix the mashed banana and maple syrup to the oat mixture until combined.
Stir in raisins, and any other add -ins you would like in your bars. (ex. Wwalnuts, Ccoconut, dates, dark chocolate)
Spoon the oatmeal batter mixture into pan. Use the back of a spoon to compress the mixture into the pan evenly, smoothing out the top.
Bake for 25 – 30 minutes, or until the top of the bars are firm and golden brown at the edges.
Let cool and cut into squares. Store in the fridge or freezer.
Warm and enjoy!