Pesto Crusted Prime Rib

With all due respect to vegetarians, nothing quite says Sunday-night dinner like roast beef … and nothing says roast beef like prime rib. To be clear, I’m not even a big beef eater — in fact, beef is my least favourite ‘meat’ well behind pork, lamb, duck or most fish — but every once in awhile I get a real craving for roast beef. My relationship with beef is also a very strong contribution to the argument of nurture vs. nature: my father is the biggest beef eater I know. Growing up, I ate roast beef often … and well. And more often than not, it was accompanied by Yorkshire pudding. My father knows how to cook a roast, devour it, and appraise it. In his opinion, the only spices you need on a good beef (vs. run-of-the-mill beef) is salt and pepper. He’s come around to some garlic as well, but the point is a good one: if you have a good cut of beef, preferably grass fed, you don’t really need much more to make it sing.

So why mess with a good thing? Well, because I think there are a few things that can take even a good singer and still produce a symphony … and when it comes to beef, those things are basil and rosemary. Both pair exceptionally well with beef —  the warm peppery aromatic qualities of basil are to beef like mint is to lamb … and speaking of things that go well with lamb, no slow-cooked Greek lamb would be the same without the slightly evergreen qualities of rosemary — and it’s an herb that works just as well with the strength of beef. And don’t forget the garlic and lots of olive oil as well.

Thus as I contemplated what to do with the roast in front of me, I considered these ingredients and I thought: pesto. Why not? It has many of these ingredients in it already, why wouldn’t it work? So I took a big bag of pesto from my freezer and decided to build it up with all the things that love beef … and I created a wet rub that I could both us to marinate the roast and which in turn would become a protective crust to seal in the juices. Mmm….

How good was it in the end? Well, let me put it this way: people were ready to abandon the beef and just eat the crust if there was more to be had … it was that good.

Cooking Tips: Marinating this overnight isn’t exactly necessary … but it sure is good. In choosing your pesto or making your own, if you have a choice, omit the cheese. It’s not necessary and it will likely brown faster (read: burn). Secondly, remove the roast from the fridge a good hour or two before you cook it. There are two reasons for this: a cold roast takes longer to cook (an extra 30-45 minutes I’d wager, depending on the size) because your fridge is 4ºC (40ºF) and you need to raise the roast to 57ºC (135ºF) for medium-rare … and so you’re already 15 degrees behind with a cold roast. The second reason is that meat is a muscle (sorry to alarm anyone who didn’t know this or doesn’t want to think about it) and like any muscle, when cold, it is tight … and the result is a tougher roast when you cook cold meat.

How to pick the right roast? Well, first, make sure it is a prime-rib aka standing-rib or rib-roast (and bone-in). Look for good marbling (i.e. specks of “fat”) throughout as this produces tenderness and flavour. There should also be a decent layer of fat on the top (opposite side of the bones) for the same reason. How big should it be? Estimate half-pound (quarter kilo) of uncooked roast per person — in other words, a 4½ lb (2kg) roast will feed 8-10 hungry people. Don’t buy anything smaller or it won’t cook evenly.

Crucial to any roast is getting it to the right internal temperature. The best tip is to use a meat thermometer if you can and, ideally, a probe thermometer you can leave in the roast while it cooks so that you don’t have to keep opening/closing the oven to check on it. No matter how good a cook you are, every roast is a bit different and starts at a different temperature (even if removed from fridge); every oven is different; and, not matter how you slice it (pun intended), without a temperature probe, you’re just guessing doneness. With a meat thermometer, well, cooking a perfect roast just got as near to idiot proof as you’re going to get: cook to 135ºF (57ºC) for medium-rare; 140ºF (60ºC) medium; 150ºF (65ºC) medium-well. If these numbers seem low, they are — but here’s the “trick.” Food doesn’t stop cooking when you remove it from the oven — the internal temperature, which is higher than room temperature, continues to cook the food. Why not serve it hot, then, right out of the oven, at the right temperature, you ask? Well, without intending to get too graphic, the “juices” in any meat run thin and loose when the meat is hot — as the meat (muscle) cools, these juices are reabsorbed. If you carve a roast of any description right out of the oven, the juices will run out and your your meat will lose both valuable flavour and moisture … and be dry. The trick to avoid this: remove the roast early, “tent” it with foil, and let it continue to cook on the counter while the juices are reabsorbed. Just 30 minutes in this state will cook the roast another 10 degrees … 10 more degrees to perfection. And when it comes to a well-cooked roast, the real goal is a slice of meat which is the same “doneness” from edge to edge to edge to edge. Now that’s perfection ….

Prep time:  10 minutes + marinate overnight
Cook time:  22 minutes per pound (medium-rare)
Rest time:  30 minutes 
Total Time: 3 hours (5 lb roast)
Servings:    8 or more (½ lb roast per serving)

Pesto Crusted Prime Rib

Ingredients:

• 4½-7 lb (2-3kg) rib roast, bone-in
• 1/4 cup (60mL) pesto (without cheese)
• 1/4 cup (60mL) fresh rosemary, coarsely chopped
• 3 cloves garlic, minced
• 3 tablespoons (45mL) dijion mustard
• 1 tablespoon extra-virgin olive oil
• 2 teaspoons fresh ground pepper
• salt (applied before cooking)

DIRECTIONS:

1. Remove leaves from rosemary and chop coarsely; mince the garlic; add both to the pesto. Add in the mustard, pepper, and olive oil until a thick paste is formed.
   → Optionally: add all these ingredients together in a small food processor and pulse until a thick paste is formed.
   
2. Don’t trim the roast of any excess fat. Your butcher (should have) left this there for a reason and it should be roughly 1/2-inch (1-2 cm) thick. Place the roast in a large ziplock freezer bag and evenly paste on the marinade-crust.
   Seal the bag and place in the fridge overnight — or minimally 2 hours.
3. Carefully remove roast from fridge 1-2 hours before roasting and place on a rack in roasting pan, bone-side down (fat-side on top) and make sure the roast is still well-covered in the pesto crust. Scoop marinade out of the bag and repair any missing spots.
   → Preheat oven to 500ºF (260ºC) 30 minutes before starting roast.
4. If you have a meat probe, poke it into the middle of roast, keeping it away from the bones. Place roast in oven and roast for 15 minutes at the high temperature (this will further seal in the juices). Reduce oven to 325ºF (160ºF) and continue cooking for 22 minutes per pound (50 minutes/kg), which includes the first 15 minutes. Continue cooking until meat probe reaches 135ºF (57ºC) for medium-rare; 140ºF (60ºC) medium;150ºF (65ºC) medium-well.
   
5. Once desired temperature has been reached, completely cover the roast with aluminium foil and let stand while you prepare your sides etc.
   
6. Remove foil and place roast on a carving board. Using a sharp carving knife, slice your roast at thickness you desire. The tricky part is carving around the “ribs” that are part of your roast … and which are there because they add tremendous flavour. You can either slice down to the bone and then under and across to liberate the meat from the bones … or, as some will tell you, you can first remove the ribs from the cooked roast and then carve the roast (the downside of this method is that you run the risk of losing more juices).
   
7. Serve with your favourite sides (e.g. gravy, roasted carrots, Yorkshire pudding, and/or scalloped potatoes) … and enjoy with any extra juices.