Step 1
Preheat the oven to 175°C (350°F). Grease a 23x23cm (9x9-inch) baking pan.
Step 2
Using an electric mixer, beat together peanut butter, brown sugar, and butter in a large bowl until creamy. Add the egg and vanilla, mixing until well combined. Stir in the mashed banana. Fold in the oats, flour, wheat germ, and baking soda until the batter is thoroughly mixed. Spread the batter into the prepared baking pan.
Step 3
Bake in the preheated oven for 20 to 25 minutes, or until the bars are set and lightly golden. Allow to cool completely in the pan on a wire rack before cutting into bars.