Roast Prime Rib With Rosemary Jus Lie

Directions

1. On cutting board, mix thyme with garlic; sprinkle with salt. Holding knife blade at very low angle, rub many times to create smooth paste. Mix pepper and cayenne; rub over roast. Wrap in plastic wrap and chill for 4 hrs. (Make-ahead: Chill for up to 24 hrs.)
2. Scatter onions and rosemary in greased roasting pan. Place roast, bone side down, on onion mix. Roast in 325 F (160 C) oven till meat thermometer inserted in centre registers 140 F (60 C) for rare, 1 3/4 to 2 hrs, or possibly 150 F (65 C) for medium-rare, 2 1/4 to 2 1/2 hrs, or possibly to desired doneness. Transfer to cutting board or possibly warmed platter; tent with foil and let stand for at least 10 min or possibly for up to 30 min.
3. Meanwhile, skim fat from pan juices; place pan over high heat. Add in wine; cook, scraping up any brown bits from bottom of pan, till reduced by half, about 3 min. In small bowl, whisk stock into cornstarch; whisk into pan and bring to boil. Boil for 1 minute; stir in butter. Strain into warmed gravy boat.
4. Slice bones off meat and separate each rib. Slice meat and arrange on platter along with ribs. Stir accumulated juices into sauce.