First, make the dough. Combine yeast and lukewarm water in the bowl of your stand mixer fitted with the dough hook. Let sit for about 5 minutes. Add butter, sugars, salt, eggs and banana and stir (using the dough hook) to combine. Gradually begin adding in the flour, one cup at a time, stirring well after each addition, but not over-stirring (you just barely want all the flour incorporated in the dough before adding more.)
Keep adding the flour until the dough can be removed from the mixer without sticking too much. It will be a little sticky, but feel free to put more flour on your hands to help you get it out of the mixer and onto a lightly floured surface. Knead the dough lightly on the floured surface, adding light dustings of flour as needed, until you feel you can roll the dough out into a large rectangle.
Using a rolling pin (or pizza roller), roll the dough into a rectangle that’s large enough for the dough to be about ¾ of an inch to an inch thick. You’ll want one of the long sides of the rectangle closest to where you are standing.
Using a pastry brush, brush the melted butter over the dough, then sprinkle on the cinnamon, followed by the walnuts and chocolate chips.
Starting at the long side of the rectangle that’s closest to you, begin rolling up the dough into one long log. Do this slowly and carefully, using a rubber spatula and more flour to guide the dough as needed. Pinch the ends into the dough to prevent the log from falling apart.
Using a sharp knife, slice the log of dough into 1 ½ - 2-inch pieces. Spray a 9x13-inch baking dish with nonstick cooking spray, and place each roll snugly side-by-side. If you have extra rolls that you can’t fit in the pan, place them in another, smaller baking dish coated with cooking spray, such as a loaf pan.
Cover rolls with plastic wrap and place in refrigerator overnight.
In the morning, take the cinnamon rolls out of the refrigerator and uncover. Preheat the oven to 250 degrees Fahrenheit for just 5 minutes, then turn it off. Add the cinnamon rolls to the warm oven for about 15 minutes to go through a second rise, then remove the rolls and turn the oven heat up to 350 degrees Fahrenheit.
Return the cinnamon rolls to the oven and bake for 30-35 minutes, or until golden brown. Remove and let cool slightly while you make the glaze.
In a medium bowl, sift together the powdered sugar and cocoa powder. Add the melted butter and milk and whisk until a thick glaze forms. Spoon the glaze over the cinnamon rolls before serving.