In a large bowl, add 2 cups of flour, sugar, dry yeast, and salt. Stir with a rubber spatula until blended.
In a microwave-safe bowl, add in the water and butter, Microwave on HIGH in 15-second increments until it reaches 120° to 130°. Use a thermometer or if a thermometer isn't available, stick your finger in the water. It should be lukewarm and not hot. The butter may not be melted completely.
Pour the water/butter mixture in with the dry ingredients.
Add an egg to the mixture. Beat with a hand mixer for 2 minutes on medium speed. Scrape down the bowl occasionally.
Add in an additional 1 cup of flour. Beat with the hand mixer on high speed for another 2 minutes. Scrape down the bowl occasionally.
Stir in the remaining flour until the dough forms into a ball.
Turn the dough out onto a lightly floured surface and knead for 6 to 8 minutes until it becomes smooth and when pressing 2 fingers into the dough it springs back.
Place back into the mixing bowl and let rest for 10 minutes.
While the dough is resting, work on the filling.
In a small bowl, stir together the cinnamon and sugar until combined. Set aside.
In a separate bowl, stir together the butter and extract until combined. Set aside.
Turn the dough out onto a lightly floured surface and roll into a 15x10-inch rectangle using a rolling pin.
Spread the butter/extract mixture on top of the dough, being sure to stop at least ½-inch from the edges.
Sprinkle the cinnamon sugar mixture on top.
Add the sliced bananas on top of the cinnamon sugar mixture. Make sure they don't overlap.
Tightly roll the cinnamon rolls beginning at the long end of the rectangle. Press the steams together to seal them.
Cut into 12 equal pieces or 8 equal pieces.
Place the cinnamon rolls in a greased 13 x 9-inch baking pan. Cover with a towel and let rise in a warm place until doubled in size, about 1 hour.
Bake in preheated 350ºF oven for 25 to 30 minutes for 12 cinnamon rolls or about 40 minutes for 8 cinnamon rolls, until the rolls are golden brown. Cool on a wire rack for at least 20 minutes.
While the cinnamon rolls are baking, add in the powdered sugar, butter, vanilla, and milk in a large bowl. Beat until creamy. If the frosting feels too stiff, add an additional 1 tablespoon of milk and beat until smooth.
Spread the frosting over hot rolls.
TIP: Use unflavored dental floss instead of a knife to cut rolls. To do, cut a piece of floss about 12 inches long. Slide floss under the roll; bring the ends up and cross over to cut each slice.