Lay 12 frozen cinnamon rolls on parchment paper for 45 min - 1 hour to slightly defrost. Preheat smoker or oven to 350 degrees.
Cut each one into 4ths, dip each piece into white sugar to coat, then lay half of coated pieces into a sprayed 8x8 aluminum disposable pan.
Melt butter, brown sugar and pumpkin together in microwave for a minute. Stir so mixture becomes smooth. Pour about half on top of the first layer of cut rolls. Add half of nuts if you want to now.
Place the remaining cut rolls on top. Set 1/2 cup butter mix to the side to put on the top once it is cooked. Then pour the remaining butter mixture on top (add remaining nuts if desired on top).
Spray the underside of a piece of foil with nonstick spray and tent over monkey bread so it can rise. Squeeze sides on to pan so edges are sealed but leave middle poofed up to leave room for it to rise quite a bit.
Put in middle of smoker grate once preheated and close lid. Allow to cook for 40 minutes.
Remove and take off foil. Use the back of a spoon to spread remaining butter/sugar mixture on top. Then drizzle packet of icing on the very top.
Set on a trivet in the middle of a table and give everyone a fork to enjoy right out of the pan. Alternatively you can loosen edges, put large plate on top and flip over. Then spread on butter mixture and squeeze on frosting so pan is removed before eating.