Step 1: Mix together kosher salt, black pepper, garlic powder, onion powder, paprika, dried thyme, and dried rosemary in a bowl to create the rub.

Step 2: Pat the prime rib roast dry with paper towels. If using bone-in prime rib, tie it with cooking twine to help it hold its shape during cooking.

Step 3: Rub the prepared spice mixture all over the prime rib, ensuring even coverage. Let the prime rib sit at room temperature for about 30 minutes to allow the flavors to meld.

Step 4: Meanwhile, fire up your Masterbuilt smoker and preheat it to 225°F (107°C). Add wood chips to the smoker box according to the manufacturer's instructions for that irresistibly smoky flavor.

Step 5: Place the seasoned prime rib on the smoker's grill grates, bone-side down if it's bone-in. Close the lid and let the magic begin!

Step 6: Smoke the prime rib at 225°F (107°C) for about 4-5 hours or until the internal temperature reaches your desired doneness. Keep an eye on that internal temperature using a meat thermometer.

Step 7: When the prime rib's internal temperature hits around 135°F (57°C) for medium-rare (adjust according to your preference), carefully remove it from the smoker and transfer it to a cutting board. Tent it loosely with aluminum foil and let it rest for about 20-30 minutes.

Step 8: During this resting phase, the juices redistribute within the meat, resulting in a succulent and tender prime rib.