Add the banana to a small bowl and mash it completely. Then measure out ½ cup and transfer it to a large bowl.
To the large bowl, add the oats, peanut butter, honey, protein powder, and cinnamon. Mix with a fork until everything is combined.
Gently mix in the mini chocolate chips.
Cover with plastic wrap and refrigerate for an hour to help the mixture firm up, making the balls easier to roll.
Scoop out 2 tablespoons of the mixture and roll it into balls about 1 ½ inches in diameter. Make sure to slightly wet your hands to prevent sticking.
Serve immediately, or place them on a baking sheet lined with parchment paper and freeze until solid. Then transfer to a freezer bag and freeze for up to 2 months.