Roasting and Finishing
2. Roast the meat: take the meat out of the fridge and preheat the oven to 400°F. Puree together the rosemary, onion, salt and olive oil, and stuff the mixture into the roast’s crevices.
3. Roll up the roast into a loose cylinder. Put it, fat side up, into a large shallow pan (we like a half sheet pan), scrape all the marinade over it, and scatter the orange slices around the pan. Roast for 30 minutes, then pour in the remaining 1 cup of wine.
4. Turn the heat down to 325°F, pour in the rest of the orange juice (2/3 cup), and roast for another 90 minutes, basting the pan juices and the orange slices over the meat several times. If the pan juices threaten to burn, blend in a little water. You want them to end up being syrupy, but not burned.
5. Test the internal temperature of the meat with an instant-reading thermometer. Once it reaches 145°F. to 150°F., reduce the heat to 200°F. for another 30 minutes, or until the meat’s internal temperature is 155°F. Remove the pork from the oven and let it rest in a warm place for 10 to 15 minutes before slicing.
6. The pan juices should be syrupy. If needed, set the pan over two burners, skim off a little excess fat, and cook down the juices, stirring with a wood spatula.
7. To serve, thinly slice the pork across the grain, moistening the slices with the pan sauce and bits of roasted orange. Don’t be put off if the meat is a pinkish beige; it is safe and so succulent. Serve the pork hot.
"Often you find that there are ways you can improve techniques or recipes," says J. Kenji López-Alt, author of The Food Lab: Better Home Cooking Through Science.