Mix together 1 1/2 cups sugar and cinnamon. Set aside.
In a small bowl, dissolve yeast and 1 tsp sugar in warm water. Set aside. (let me interject here. i actually did not do this. i just ended up adding in my Instaferm Instant Yeast that i use to bake bread into my mixer with the flour. I still added the water in too, but with Instant yeast, you don’t have to let it dissolve in perfect temperature water first…you can just add it in! i get mine through www.breadbeckers.com, but you can certainly follow this recipe and use the active dry yeast too.)
In a mixer, mix milk, 2/3 cup sugar, 2/3 cup melted butter, salt, and eggs. Add in the yeast mixture (or just instant yeast and 1 cup water) and 4 cups flour. Mix well. Keep adding flour until you get a slightly stiff dough (when it stays together, pulls away from the sides of the bowl, and is elastic). Put on dough hook and let knead for 8 minutes, or knead by hand.
Place dough in large greased bowl, cover, and let rise until double, about 1-1 1/2 hours.
Punch down and let rest for 5 minutes.
Roll out dough on a floured surface to a 15 x 20 inch rectangle.
Brush with 1/2 cup melted butter and sprinkle the cinnamon sugar mixture evenly over dough. (Sprinkle nuts at this point, if using).
Tightly roll up dough and pinch edges together to seal. (note: wish i had rolled tighter, so roll as tight as you can!)
Cut into 12-15 slices. (i got 13.) Use either a pastry cutter, dental floss, or thread for this. a knife squishes them too much.
Coat the bottom of a 13 x 9 baking pan with 1/2 cup melted butter and 1/3 cup sugar. (this part is important in keeping the rolls moist, so don’t skip. just use the butter and don’t eat them everyday!!)
Place roll slices close together in pan.
Cover and let rise in warm place for 45 minutes. (another note: i ran out of time the night i made these, so at this point, i put them in the fridge on Friday evening and then took them out Sunday morning, let them sit for a while on the counter, and then baked them. worked great!)