Christmas Day kind of got away from us this year. Many of our elaborate plans for the meal we were cooking for ourselves vanished, as we learned that, in Maine, all. grocery. stores. close on Christmas day. We had been counting on being able to rush out on Christmas day to pick up some of the final ingredients we needed. Not so. I did manage to score a box of Triscuits from a Walgreen’s out on Forrest Ave., but that was the best I could come up with.
Luckily, we had this beautiful prime rib roast gurgling away in the oven. The mustard formed a nice crust around the outside of the meat, the dijon créme fraîche can be slathered on absolutely anything, and the onions turned out beautifully. Next time, I will be sure to leave the root ends of the onions attached, so that we end up with little onion chunks that tenderize perfectly and can be cut beautifully; mine kind of shredded and got overcooked.
Speaking of overcooked, you’ll see in the photo that I overcooked the roast slightly. You need to take it out of the oven when the internal temp reaches 120 degrees, since it will increase another 10 degrees to a perfect medium rare as it rests. The roast got away from me, and went from 110 degrees to around 126 degrees in just a few minutes, before I frantically pulled it. Ours wasn’t completely ruined, but I see how easy that would be to do. Keep a close eye on temperature during the last few minutes of cooking.
Mustard-Crusted Standing Rib Roast w/ Dijon Créme Fraîche and Roasted Balsamic Onions
Adapted from a recipe in Bon Appetit
- 1/4 cup crème fraîche
- 1/4 cup heavy whipping cream
- 2 tablespoons prepared white horseradish
- 1 cup plus 1 teaspoon Dijon mustard, divided
- 4 medium onions, cut into 3/4-inch wedges with some root attached
- 5 very large shallots (about 1 pound), quartered through root end
- 3 tablespoons balsamic vinegar
- 2 tablespoons olive oil
- 1 1/2 teaspoons coarse kosher salt plus additional (for sprinkling)
- 4 garlic cloves, minced
- 1 7-pound bone-in standing prime rib roast, trimmed
- 2 tablespoons yellow mustard seeds
Beat crème fraîche and cream in medium bowl using electric mixer, until stiff peaks form. Fold in horseradish and 2 1/2 tablespoons mustard. Season to taste with salt and pepper. Cover and chill.
Preheat oven to 450°F. Toss onions, shallots, vinegar, oil, and 1 1/2 teaspoons coarse salt in large bowl. Sprinkle roast lightly with coarse salt and generously with pepper. Stir 2/3 cup mustard and garlic in small bowl; rub over roast. Place roast, bone side down, in roasting pan. Sprinkle mustard seeds over, pressing to adhere. Roast 20 minutes. Reduce oven temperature to 350°F.
Arrange onion mixture around roast. Return to oven; roast until instant-read thermometer inserted into center registers 120°F, stirring onion mixture occasionally, about 2 hours for medium-rare.
Transfer roast to work surface. Tent with foil; let rest 30 minutes. Slice roast; arrange on platter. Spoon onions around roast. Serve with Dijon Créme Fraîche.