Preheat oven to 350 degrees and line muffin tin with papers.
Mix base per recipe instructions on box, set cinnamon swirl packet aside, and then stir in mashed bananas and walnuts until well combined.
Scoop 1 tablespoon of batter into muffin paper and then sprinkle on cinnamon swirl mix. Then add more batter to fill the paper ¾ of the way full.
Bake 20-25 minutes until a toothpick comes out clean.
Cool completely and then frost with the cream cheese frosting and garnish with the cinnamon swirl mix.
Serve and enjoy.