Warm milk to 110 degrees in a small bowl. Then add active dry yeast and a teaspoon of granulated sugar, which helps to activate it. Allow to sit for 10 minutes until yeast is frothy.

Mash bananas and set aside.

Then add the yeast mixture to the bowl of your stand mixer, fitted with the dough hook attachment.

Add the egg yolk and granulated sugar and mix on low speed, until combined before adding the bananas.

Then melt butter and add that along with salt to the mixture.

Gradually add the flour. Start with 3 3/4 C of flour. Dough will be sticky. If it is too wet then add another 1/4 C.

Then turn mixer up to medium high and mix dough for 10 minutes.

Meanwhile, butter a large bowl. Once dough is ready, turn into the bowl. Cover loosely and allow to rise for 90 minutes, or until doubled.

Punch down the dough.

Butter a 9 x 13 pan. Or you can use parchment paper to line it.

Sprinkle flour onto your counter and put dough on it. Roll into a rectangle that is 14 x 16 inches. Spread butter over the surface.

In a small bowl, mix cinnamon and nutmeg with dark brown sugar. Sprinkle over butter. Then gently rub it in a bit with your fingers.

*If you want more banana flavor, then feel free to top with banana slices and optional nuts.

Then tightly roll up the dough, starting with the shorter side. Make sure the log is seam side down, Then, use a knife to slice off 1 inch from each side. This removes dough that didn't get enough of the filling and looks better when baking.

Slice 12 one inch pieces. Set into pan.

Cover loosely with plastic wrap. Allow to rise another 30 minutes.

Preheat oven to 350 degrees F. Bake for 26-30 minutes. Cool for 10 minutes before frosting.

Make frosting using an hand mixer or stand mixer with paddle attachment. Beat butter and cream cheese until smooth. Then scrape down bowl and add powdered sugar and vanilla. Beat until creamy. Spread over cinnamon rolls.