Slow-Roasted Prime Rib with Cajun Spice Rub
A tender 12 oz prime rib ribeye seasoned with a bold Cajun spice blend, slow-roasted to a perfect medium doneness and served with pan juices. This american-inspired beef ready in about 60 minutes pairs prime rib ribeye, Cajun seasoning, kosher salt for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 650 calories and feeds 2, so it slots cleanly into a weekly meal plan and pairs well with a quick salad or grain on the side. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.
Ingredients
- 12 oz prime rib ribeye
- 2 tbsp Cajun seasoning
- 1 tsp kosher salt
- 1 tsp black pepper
- 1 tbsp olive oil
- 3 cloves garlic cloves, minced
Equipment for this recipe
Top-rated tools to make this recipe successfully.
Instructions
- Step 1: Preheat your oven to 275°F (135°C). In a small bowl, combine 2 tbsp Cajun seasoning, 1 tsp kosher salt, 1 tsp black pepper, and 3 minced garlic cloves.
- Step 2: Rub 1 tbsp olive oil all over the surface of the 12 oz prime rib ribeye, then evenly coat it with the Cajun spice mixture, pressing it into the meat to adhere.
- Step 3: Place the ribeye on a wire rack set inside a baking sheet and roast in the oven for about 40-50 minutes, or until the internal temperature reaches 130°F (54°C) for medium rare.
- Step 4: Remove the ribeye from the oven and tent loosely with foil. Let it rest for 15 minutes before slicing to allow the juices to redistribute.
- Step 5: Slice against the grain and serve with the pan juices drizzled over the top.
Frequently asked questions
How long does Slow-Roasted Prime Rib with Cajun Spice Rub take to make?
Total time is about 60 minutes (10 min prep + 50 min cook). Most home cooks find this fits comfortably into a weeknight; double the batch on Sunday for two dinners.
How do I store leftover Slow-Roasted Prime Rib with Cajun Spice Rub?
Cool to room temperature within 2 hours, then store in an airtight container in the fridge for up to 4 days. Reheat covered in a 350°F oven for 10-12 minutes, or microwave at 70% power in 60-second bursts to keep prime rib ribeye from drying out.
Can I substitute ingredients in Slow-Roasted Prime Rib with Cajun Spice Rub?
Yes — most ingredients in this recipe have flexible swaps. For oil, use any neutral high-smoke-point oil (avocado, grapeseed, refined coconut). For aromatics, dried herbs at ⅓ the volume of fresh work in a pinch. The full ingredient list is shoppable on Instacart so you can see substitutes in real time.
How do I scale Slow-Roasted Prime Rib with Cajun Spice Rub for a different number of people?
The recipe is written for 2 servings. Multiply each ingredient by (your serving target / 2). Cook time stays roughly the same up to 2x; for 3-4x batches, switch from a skillet to a sheet pan or stockpot so the food isn't crowded — overcrowding steams instead of browns.
What goes well with Slow-Roasted Prime Rib with Cajun Spice Rub?
American beef like this pair well with a simple grain (rice, couscous, or crusty bread), a quick salad with acid (lemon vinaigrette, pickled onions), and a pan sauce or yogurt-based dip. Tap "Plan a meal with the AI" to get specific side suggestions.