Cajun Prime Rib Roast
Move over traditional prime rib – this Cajun prime rib brings BOLD flavor to your holiday table! Injected with Cajun butter and coated in spicy seasoning, this prime rib roast is packed with flavor from edge to edge, not just on the crust. After smoking hundreds of prime rib roasts, this is hands down the most flavorful one we've ever made!
Servings: 8 people
Equipment
- butcher's twine
Ingredients
For the Prime Rib:
- 6-7 pound prime rib roast boneless or bone-in
- 1 cup bottled Cajun butter injection marinade like Zatarain's or Tony Chachare's
- 1/4 cup Cajun or Creole seasoning for dry brining roast
- ½ cup unsalted butter softened
- 2 tablespoons Cajun or Creole seasoning for the butter mixture
For the Potatoes and Onions:
- 1½ pounds baby yellow potatoes washed and dried
- 8-10 Cipolline onions peeled (or 1 large sweet onion, peeled and cut into chunks)
Optional Blue Cheese Sauce:
- 1/2 cup heavy cream
- 5-6 cloves roasted garlic mashed
- 3-4 oz blue cheese crumbles
Instructions
Day Before:
- Truss the roast. Tie the prime rib roast with butcher's twine in three places (or about every 2") to keep it together during cooking.
- Season generously. Cover all sides of the roast with about ¼ cup of Cajun seasoning spread out evenly. This acts as a dry brine.
- Refrigerate overnight. Place the seasoned prime rib roast on a wire cooling rack on top of a sheet tray. Place in the refrigerator uncovered overnight.
Day Of:
- About 2-3 hours before cooking, inject the roast with Cajun butter. Using a meat injector, inject the roast all over with Cajun butter marinade, using about one full syringe per quarter section. Use the same hole for multiple angles to avoid over-poking the meat. Total amount of injectable marinade should be about 1 cup for a 6-7 pound roast.
- Prepare the roasting tray. Place baby potatoes and onions in the bottom of a roasting pan or deep-sided sheet tray, spread out in a single even layer. Set a wire rack on top. This catches the drippings and flavors the potatoes and onions.
- Make and apply the Cajun butter. Mix 1 stick of softened butter with 2 tablespoons Cajun seasoning until well combined. Slather the Cajun butter mixture all over the prime rib roast, making sure to coat all sides generously. Place the roast on the wire rack over the vegetables.
- Preheat grill or smoker. Heat your pellet grill, charcoal grill, or smoker to about 250°F with your choice of wood or pellets.
- Smoke the prime rib. Place the sheet pan with vegetables and prime rib roast on the grill. Close the lid and smoke at 250°F until internal temperature reaches 117-118°F, about 3-4 hours depending on size and grill temperature.
- Remove and increase heat. When the roast reaches 117°F, remove the wire rack with the roast from the grill. Increase grill temperature for searing. *NOTE - If the potatoes are not done yet, you can leave the tray with the potatoes and onions on the grill while the grill is heating to a higher temp. Use an instant-read thermometer to check potatoes – they should reach 208-210°F.
- Sear the roast. Once the grill is very hot (about 400-450℉), return the prime rib to the grill and sear on all sides until a nice crust forms and internal temp reaches 120°F, about 10-15 minutes total. *NOTE - Removing the Cajun prime rib at 120℉ allows for about 5-6 degrees of carryover cooking for a perfect medium-rare. For a higher doneness, cook to a higher internal temperature, keeping in mind that the carryover cooking could result in about 5-10 degrees more of doneness.
- Rest and carve. Remove the Cajun prime rib roast from the grill, and let rest for 15-20 minutes. Cut away the butcher's twine and carve the roast into 1/2" to 1" thick steaks.
- Serve immediately. Plate the Cajun prime rib with the Cajun butter potatoes and onions. Drizzle or serve the blue cheese sauce on the side (optional).
- Make blue cheese sauce (optional). While the roast is resting, warm heavy cream with mashed roasted garlic in a small saucepan. Add blue cheese and stir until melted.
Notes
- Cooking Time Note: The cooking times in this recipe are provided as a guide only and could vary based on roast size, grill temperature, etc. Always cook to the proper internal temperature, not to a specific time.
- Important Temperature Tip: Because we finish this roast with a high-heat sear, there's more carryover cooking than with a low-and-slow finish. Plan to pull your roast 5-10 degrees lower than your target final temperature.
- Trussing is Essential: Don't skip the trussing step! The fat separation between the spinalis and the eye can cause the meat to fall apart, especially with the moisture from the injection.
- Salt-Forward Seasoning: Most Cajun seasonings are very salt-heavy. This replaces a traditional salt brine, so there's no need to add additional salt.
- Potato Done-ness: Potatoes are perfectly done at 208-210°F internal temperature. They should be fork-tender.
- Storage: Leftover prime rib can be stored in an airtight container in the refrigerator for up to 3 days. Great for steak sandwiches!