• Begin by warming the milk and melted butter in a sizable microwave-safe bowl. Microwave for approximately 40 seconds until it reaches 110°F (45°C), then mix in the yeast and set aside for 10 minutes.

For Dough:

• Stir in the granulated sugar, salt, and mashed bananas until everything is well blended.
• Slowly incorporate 3½ cups of flour, adding half a cup at a time, ensuring thorough mixing at each step.
• Transfer the dough to a floured surface and knead for around 3 minutes. If the dough sticks too much, gradually sprinkle in additional flour until it holds its shape.
• Drizzle oil into a clean large bowl, place the dough in it, cover with a kitchen towel, and refrigerate for a minimum of 3 hours or overnight until it doubles in size.
• Once the dough has risen, roll it out into a rectangle about ¼ inch thick, approximately 18x12 inches.

For Filling:

• In a small bowl, combine the melted butter, ¼ cup granulated sugar, and cinnamon for the filling.
• Spread the filling uniformly across the rolled-out dough. Roll it tightly and cut it into 15 pieces, each around 1½ inches thick, discarding the ends.

For Caramel Sauce:

• In a small saucepan over medium heat, combine butter, brown sugar, salt, vanilla, and honey. Stir continuously to prevent sugar from sticking. Bring to a gentle boil before removing from heat.
• Pour the caramel sauce into a 9x12-inch baking dish and top with the walnuts. Arrange the sliced rolls in the dish in 3 rows of 5.
• Cover the dish with plastic wrap and let the rolls rise in a warm area for about 15 minutes.
• Preheat your oven to 350°F (180°C).
• After removing the plastic wrap, bake the cinnamon rolls for around 40 minutes, or until they achieve a light golden brown color.
• Let the rolls cool for 20 minutes before carefully inverting them onto a serving platter.