Prepare the dough: Warm up milk to be warm to the touch (not hot, think baby bath water or about 110° F) Using a stand mixer* with a dough hook, combine the warm milk (not scalding hot, but warm to the touch), yeast, and sugar together. After a couple minutes, you should see the yeast starting to foam - that means its activating!
Add your first 3 cups of flour and mix together. Once it's mostly incorporated, add softened butter, eggs, and salt. Continue to mix on low.
Slowly add the additional 2 ½ cups of flour. In pouring your last cup, do so slowly, watching the dough. Add additional flour as needed, just a little at a time. When you've added enough flour, the dough will be soft and slightly sticky. It will also be pulling away from the bowl. You don't want a tough dough. Leave the mixer on for an additional 8-10 minutes to knead.
Take your dough hook out, and cover the bowl to let the dough rest and rise for about 30-40 minutes.
Filling: Mix together melted butter, sugar, and orange zest. Set aside.
Assembly: When the dough has about doubled, punch it down and place on a clean, floured work surface. Use a rolling pin to roll the dough out into about a 14x18 inch rectangle, making sure the dough is smooth and even in the corners. Spread an even layer of the filling.
Tightly roll it up into a log. You can roll either direction. I like to roll from the short end to make a nice thick log. Rolling from the long end will create a slightly skinnier, longer log which will yield more rolls. Cut with a strand of floss into 1 inch sections and place in a greased jelly roll pan or baking pan, leaving about 1-2 inches in between so the rolls have room to grow. You should get about 15-20 rolls depending on how thick you make them. You can also make these into mini rolls. Rest & Bake: Overnight Instructions: Cover well with sprayed plastic wrap and let them rest in the fridge overnight. The next morning, preheat the oven to 350°F and let the rolls get back to room temperature and rise (usually takes about 1 hour). Baking immediately: Keep the rolls in a draft free place and let them rise until they've grown and the dough gets soft and puffy, usually about 25 minutes. While they're resting, preheat the oven to 350°F. Bake for 15-20 minutes. I like to cover them with foil about half way through so they don't brown as much on top. They're done when the tops and bottoms are starting to get lightly golden and it doesn't look doughy. Glaze: Using a hand mixer, start by beating together the butter and powdered sugar. Add remaining glaze ingredients and beat again to form a thick glaze. Add milk as needed to create desired consistency. Gently spread glaze over warm sweet rolls.
Storing: Store airtight for up to 5 days. You can freeze them, but I recommend freezing the rolls plain and adding the glaze day of for best results. Heat up slightly before serving for the ultimate gooey treat! Enjoy!