In a medium saucepan, heat milk, butter, and sugar until butter is melted and the temperature is 120°F - 130°F. Remove from heat.

In a bowl of a stand mixer with a paddle attachment, beat together 4 ½ cups flour, yeast, and salt. Add melted butter mixture and mashed bananas; stir to combine until a shaggy dough forms.

Knead the dough with a dough hook attachment at medium speed for 6-8 minutes. Add additional flour if the dough is too sticky.

Lightly grease a large bowl, place dough inside, cover, and let rise until doubled in size, about 1 to 1 ½ hours.

Turn the dough onto a lightly floured surface and roll it into an 18x12-inch rectangle.

Spread the dough with softened butter, leaving about a ½-inch border at the top. In a small bowl, combine brown sugar and cinnamon; sprinkle over butter and press down lightly. Place banana slices on top.

Starting from the long edge, roll the dough tightly into a log and pinch to seal. Cut the log into 12 equal rolls.

Grease a 9x13 baking dish and place the rolls spiral side up. Cover and let rise in a warm place for 45 minutes until puffy.

Preheat oven to 350°F (177°C). Pour slightly warmed heavy cream over the rolls and bake for 30-35 minutes until golden brown. Let cool in the pan for about 20 minutes.

In a large mixing bowl, beat cream cheese and butter together on medium-high speed until smooth and combined.

Gradually add powdered sugar and mix on low speed until combined. Add vanilla extract and beat on medium-high speed until fluffy.

Spread the cream cheese icing over the cinnamon rolls while they are still slightly warm.