In a large bowl, mix together 2 cups of flour, brown sugar, yeast, cinnamon, and salt. Stir until combined.
In a microwave-safe bowl, heat the milk and butter together for 30 seconds until the mixture is warm and the butter is mostly melted. The mixture should feel warm to the touch, but not hot. If it's too hot, let it cool slightly before adding it to the yeast to avoid killing the yeast. Add the warm milk, butter, and mashed banana to the flour mixture.
Beat the mixture on low speed, gradually increasing to high, until fully combined, about 2 minutes.
Scrape down the sides of the bowl and add another cup of flour. Beat until well combined, then slowly add the final cup of flour a little at a time until the dough begins to pull away from the sides of the bowl and forms a ball.
Turn the dough out onto a floured surface and knead for about 10 minutes until smooth and elastic. You should be able to stretch a piece of dough between your fingers without it breaking, which indicates the gluten has developed.
Place the dough in an oiled bowl, cover it, and let it rise in a warm place for about 1 hour or until it has doubled in size.
While the dough rises, prepare the filling. In a small bowl, mix together the brown sugar, cinnamon, and salt. Set aside.
Once the dough has risen, roll it out on a floured surface into a rectangle about 18 x 12 inches.
Spread the softened butter over the dough all the way to the edges. Evenly sprinkle the sugar mixture over the butter, pressing gently to ensure it sticks.
Starting from the long edge, roll the dough up tightly away from you, pinching the bottom edge to seal the dough.
Using dental floss or a sharp knife, cut the dough into 12 even rolls. Place the rolls in a 9 x 13-inch pan lined with parchment paper. Cover loosely with a dishcloth and let them rise for another hour until puffed up and doubled in size.
Preheat the oven to 350°F and bake the cinnamon rolls for 30 minutes or until they are golden brown and fully cooked through. Let the rolls cool.
While the rolls are cooling, prepare the cream cheese frosting. In a stand mixer with the whisk attachment, combine the cream cheese, butter, powdered sugar, milk, salt, and vanilla extract. Beat on low speed, gradually increasing to high until the mixture is light and fluffy.
Once the rolls have cooled slightly, spread the frosting evenly over the top. Serve warm and enjoy!