Add flours to bowl of a stand mixer. Stir together.
Whisk egg, milk, and starter together in separate bowl until starter is no longer lumpy.
Attach hook to mixer, and turn on on speed 2 of your Kitchenaid, and gradually add liquid ingredients, until all dry bits are gone. When most of the flour is absorbed turn the mixer up one level to knead for 30 seconds. Mixture will not look smooth, just shaggy. Let sit for 15 minutes.
Turn mixer onto speed 2 (using Kitchenaid Stand Mixer) add sugar, salt, and one chunk of butter at a time to the dough, only adding another chunk once the previous is incorporated into the dough. Keep doing this until all the butter is added to the dough.
Once all the butter is in the dough, turn KitchenAid up to speed 4 and continue kneading for 8 minutes, until dough is smooth, and cleaning the sides of the bowl. It will be sticky to the touch.
Overnight rise: Once kneading is done, place the dough in a bowl and put bowl inside plastic shopping or garbage bag, or alternatively cover with a very damp cloth. Leave overnight on counter at room temp to rise until double and puffy, about 10 hours if your home is at 68-70 degrees F. It will take longer if your home is cooler, less time if your home is warmer so plan accordingly.
In the morning, check your dough. It should have doubled and be domed on top. Turn it out onto a heavily floured counter. Gently pat it into a rectangle shape and let rest with a linen over the top, while you make the caramel.
To make caramel, melt butter in a saucepan. Add remaining ingredients except pecans, and bring to a boil, whisking to help dissolve the brown sugar. Once it is at a boil, turn down to a simmer for 5 minutes, until caramel is nice and brown, glossy, and smells butterscotchy. Pour into a 9x13 pan, and sprinkle with 3/4 cup pecans. Set in refrigerator to cool for 15-20 minutes, propped on a cooling rack.
Using a floured rolling pin, roll your dough it into a large rectangle roughly 16″x 12. Brush the butter onto the dough, keeping 1/2" away from edges. Mix the remaining fillings ingredient together, then sprinkle evenly on top of the butter, keeping 1/2" away from edges.
After spreading the filling, use your bench scraper to help your hands begin tightly rolling up the dough into a log, starting with the long edge closest to you. Use a little extra flour on the bench scraper each time to help pick the dough up from the surface. Don’t worry if it sticks a little, just use a little more flour dust. Roll it to the top and pinch the bottom edge of the dough log to seal it.
You should have a long log of dough roughly 16-18″ long. Now cut the dough log with your bench scraper
, at about 2 1/2 inch pieces” and set pieces into the pan with the caramel swirl side up, making sure the caramel has had 15-20 minutes in the refrigerator.
Place the pan inside a clean garbage bag and fold the opening over so that no air gets inside. Leave on counter, preferably a warm spot, to proof for 3ish hours so that the buns expand, puff up, and are touching each other. You can see photo of what they should look like above in post.
When the rolls are done proofing, preheat oven to 375 degrees F. Bake for 35 minutes, or until rolls are golden brown at the edges and set in the middles. You can use a thermometer to test their interior, which should be at 205 degrees F.
Remove pan from oven and let sit for 5 minutes. Then take parchment paper that is larger than your pan, and set on top of rolls. Place a large baking sheet on top of that. Then, using oven mittens slide your hands underneath the pan, and holding the top of the baking sheet and bottom of the baking pan, flip over so that the baking pan is now upside down. Using oven mitts, lift the baking pan off the rolls, jiggly it and patting top if needed, and your sticky buns will emerge! Scrape out all extra caramel in the pan and place on top of all rolls. Enjoy warm.
Caramel rolls will stay good in the refrigerator enclosed in a container, for 3 days. Reheat in microwave for 15 seconds.