In a bowl, whisk together all of the ingredients except salt, pepper, and the pork. Whisk in 1 teaspoon each of salt and pepper. Transfer the marinade to a large resealable plastic bag and add the pork. Seal the bag and turn to coat; set in a baking dish and refrigerate overnight.

Preheat the oven to 425°F and set a rack over a rimmed baking sheet. Transfer the pork to a work surface; discard the marinade. Fold the pork under itself, into thirds if necessary, and tie with string to form a neat roll. Season all over with salt and pepper and set it on the rack.

Roast the pork for 30 minutes, until lightly browned. Reduce the oven temperature to 375°F and roast for 1 hour and 30 minutes longer, until an instant-read thermometer inserted in the center registers 160°F; transfer to a carving board and let rest for 30 minutes. Discard the string before slicing across the grain.