01 - In a large mixing bowl, blend warm milk with active dry yeast and let stand for 5 minutes until frothy. Mix in melted butter, mashed bananas, granulated sugar, egg, and salt until well incorporated.
02 - Gradually add all-purpose flour to the wet mixture, stirring until a shaggy dough forms. Knead for 8 to 10 minutes by hand or with a stand mixer fitted with a dough hook until dough is smooth and elastic.
03 - Transfer dough to a lightly greased bowl, cover with a clean towel or plastic wrap, and leave in a warm, draft-free location for 1 hour or until doubled in size.
04 - In a small bowl, combine brown sugar, ground cinnamon, and nutmeg. Reserve. On a floured surface, roll dough into a 16-by-12-inch rectangle.
05 - Spread softened butter evenly over the rolled dough. Sprinkle cinnamon-sugar mixture uniformly on top. Starting from a long edge, roll the dough tightly to form a log.
06 - Cut the log into 12 even slices. Place rolls cut-side up in a greased 9-by-13-inch baking dish.
07 - Cover rolls and let rise for 30 to 45 minutes at room temperature until puffy.
08 - Preheat oven to 350°F. Bake rolls for 22 to 25 minutes until golden brown.
09 - While rolls bake, beat softened cream cheese, softened butter, powdered sugar, milk, and vanilla extract in a bowl until smooth and spreadable.
10 - Cool rolls for 10 minutes, then spread icing evenly over the warm rolls. Serve immediately.