For the dough: Heat the milk, oil and granulated sugar in a medium saucepan over medium heat to just below a boil. Set aside and let cool to warm.
Sprinkle the yeast on top and let it sit on the milk mixture for 1 minute. Add 4 cups of the flour. Stir until just combined, then cover with a clean kitchen towel and set aside in a relatively warm place for 1 hour.
After 1 hour, remove the towel and add the salt, baking powder, baking soda and remaining 1/2 cup flour. Stir thoroughly to combine. Use the dough right away or place in a mixing bowl and refrigerate for up to 3 days, punching down the dough if it rises to the top of the bowl. (The dough is easier to work with if it's been chilled for at least an hour or so beforehand.)
To assemble the rolls: On a floured baking surface, roll the dough into a large rectangle, about 30 inches by 10 inches. The dough should be very thin.
Preheat the oven to 325 degrees F.
For the filling: Pour the melted butter over the surface of the dough. Use your fingers to spread the butter evenly. Sprinkle over the granulated sugar and cinnamon. Don't be afraid to drizzle on more butter or more sugar! Gooey is the goal.
Now, beginning at the end farthest from you, roll the rectangle tightly towards you. Use both hands and work slowly, being careful to keep the roll tight. Don't worry if the filling oozes as you work; that just means the rolls are going to be divine. When you reach the end, pinch the seam together and flip the roll so that the seam is face down. You'll wind up with one long buttery, cinnamony, sugary, gooey log. Slip a cutting board underneath the log and, with a sharp knife, make 16 equal slices.
For the smear and base: Cream together the brown sugar, butter, honey and salt until lightened, then slowly add the whiskey and vanilla while mixing.
Butter a 12-inch cast-iron skillet, layer the bottom with the pecan pieces and then scoop 5 large scoops of the smear on top. Heat in the oven until the smear is slightly foamy and bubbling, 10 to 15 minutes.
Remove the skillet from the oven and place the sliced rolls on top of the melted smear (it's fine to put them on the hot smear). Allow the rolls to rise for 20 minutes.
Return the skillet to the oven and bake until the rolls are golden brown and the smear is brown and sticky, 20 to 30 minutes. Take another 12-inch skillet and place it on top of the hot skillet. Flip over quickly and carefully. All of the caramelly, boozy goodness will be on top.