Wagyu Prime Rib of Beef

Wagyu Prime Rib of Beef

We went ALL OUT with this Wagyu Prime Rib of Beef - a.k.a. "the motherlode". Let's see if this baby lives up to the hype, by cooking it to perfection, low and slow on the egg.

What you’ll need

The Prep

If there's one thing that can make or break a great cook, it's trimming the cut before anything else. Some will cut too much off, wasting a lot of tasty meat - others will leave too much on there, ending up with tough, unrendered fat and silverskin. 

The art is in knowing what is good. Remove any silverskin and hard fat you can feel on the fat cap of the prime rib. These will not only taste terrible on your plate but will prevent the smoke from getting to the good meat during cooking.

Spicing it up

Next, it's time to add some flavor. For this cook, we went with a combo of our home brand SPG and Texas Beef, which will complement and bring out the beefy flavor that's already in there. 

Cover all sides with a layer of Texas Beef, then repeat with SPG. Make sure you don't miss the sides! And keep in mind, the prime rib is a big chunk of meat, so it can take quite a lot.

The Cook

While we were prepping the prime rib, we had our smoker already set up and coming up to cooking temperature at 250ºF (121ºC). On the Big Green Egg, we installed the deflector plate to block out direct heat, cooking by convection (or indirect heat) instead.

Once we put the prime rib of beef on there, things can move quite fast, so keep an eye on that core temp! The target is a clean 120ºF (49ºC) in its center, but feel free to adjust this depending on how well done you want the beef.


The prime rib hit 120ºF core temp - it's time for the other thing that people often overlook: resting. Get the beef off the heat, and wrap it in a sheet of aluminum foil. Then wrap it in a towel - this will trap some of the heat inside, allowing the meat to cook just a little further, while also reabsorbing its juices.

Let the meat rest for about 30 minutes before unwrapping. Do not, I repeat, do not lose the juices! Make sure to save them as you unwrap the foil, they make for a mean sauce or jus. 

Your prime rib of beef is ready - just slice and serve, garnished with your favorite side.

Have fun!


Submit your own recipe. Embrace greatness.

Have you worked with Kosmos for a while, and come up with something even better? Many of our recipes are submitted by our wonderful customers, who come up with all sorts of ideas that we could never think of.

Go here to submit your own recipe. If accepted, you'll get 10% off the whole store.

Also in Recipes

Texas Pepper Steak

Experience the bold flavors of Texas with our mouth-watering Texas Pepper Steak. Follow these simple steps to create a juicy, flavorful steak that will impress your guests every time.

Overnight Brisket on a Pellet Cooker

A complete beginner's guide to cooking the perfect overnight brisket on a pellet grill! Learn how to get that perfect bark with juicy meat every single time.
Homemade Beef Chorizo Quesadillas

These homemade beef chorizo quesadillas are nuclear hot - don't let that dissuade you from making a lot of them! With a rich blend of spices and tender beef, this recipe will quickly become a family favorite.

Everyone wishes that they could have award-winning competition BBQ at their backyard barbecue parties. With Kosmo’s BBQ, that's exactly what you'll have, every time.