Slow-Roasted Prime Rib with Rosemary and Dijon Crust

By AislePrompt Editorial · ·

How this recipe was made — this recipe was drafted by AislePrompt's AI-assisted pipeline from technique templates and USDA-sourced nutrition data, and published by AislePrompt Editorial — see how AislePrompt recipes are developed and reviewed.

Prime rib slowly roasted with a fragrant rosemary and Dijon mustard crust, yielding a tender interior and flavorful crust perfect for festive dinners. This American-inspired Christmas recipe, ready in about 225 minutes, pairs prime rib roast, Dijon mustard, fresh rosemary, chopped for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 620 calories and feeds 6, 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.

Prep: 15 min Cook: 210 min Serves 6 American cuisine 620 cal/serving
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Ingredients

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Instructions

  1. Step 1: Preheat oven to 250°F. In a small bowl, mix 1/4 cup Dijon mustard, 3 tablespoons chopped fresh rosemary, and 4 minced garlic cloves until combined.
  2. Step 2: Pat dry 5 lbs prime rib roast with paper towels, then rub all over with 1 tablespoon kosher salt, 1 tablespoon black pepper, and 2 tablespoons olive oil.
  3. Step 3: Spread the Dijon-rosemary mixture evenly over the entire roast, pressing gently to adhere.
  4. Step 4: Place roast on a rack in a roasting pan and insert an oven-safe meat thermometer into the thickest part.
  5. Step 5: Roast in the preheated oven for 3 to 3 1/2 hours, or until the internal temperature reaches 125°F for medium rare.
  6. Step 6: Increase oven temperature to 500°F and roast for an additional 10 minutes to develop a crust.
  7. Step 7: Remove roast from oven and tent with foil; let rest for 20 minutes before slicing thinly against the grain and serving.

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