Home cooks can get fussy when preparing a Snake River Farms American Wagyu tenderloin roast. Last weekend at the International Association of Culinary Professionals conference in Los Angeles, Kenji Lopez-Alt showed us how to make Lomo al Trapo – a simple, but spectacular way to prepare this high-end cut of beef using just kosher salt, a cotton towel and a bed of red-hot coals.
Lomo al Trapo is a Colombian dish which translates to “beef tenderloin in a towel.” Although the description doesn’t sound appetizing, we had the opportunity to try it prepared by Kenji and we were impressed. We can’t wait to try it out on our friends and family. For the IACP lunch, Kenji served the beef with a bright chimichurri sauce and fingerling potatoes boiled in heavily salted water. This combo makes a simple and delicious meal.
1 Snake River Farms Center Cut Tenderloin Roast (about 1.5 lbs.)
2 pounds kosher salt
You’ll also need butcher’s twine and a simple cotton towel. Kenji says any towel will work, but it must be 100% cotton. You don’t want any synthetic fibers spoiling your tenderloin.
Rinse cotton towel in water and wring out so it is still damp. Lay towel on counter or cutting board and cover with a thick layer of kosher salt, leaving a gap of 2″ on either side.
Place the tenderloin on top of the salt and line up with the bottom edge.
Pick up the edge of the towel and fold it over the tenderloin. Carefully roll the beef in the towel so an even layer of salt covers it and the towel remains tight. When you reach the end, hold the roll and tie each end shut with a piece of butcher’s twine.
Fold the ends of the towel over and secure the whole package with a 5 or 6 pieces of twine spaced at about 2″ intervals. Kenji used a butcher’s knot using a single piece of twine, but he says that individual lengths of twine tied up with a granny knot works just fine.
Start a good amount of charcoal going on your charcoal grill. Once all the coals are fully lit, spread the coals over half the cooking grate. Place the tenderloin/towel package directly onto the coals. Cook on one side for about 10 minutes, then flip the package over. To quote Kenji” It will look like it’s burnt to all hell. This is fine and normal.”
As we always recommend, use a good instant-read thermometer to test for doneness. Firmly press through the towel and find the center of the roast. Shoot for 95°F for rare or 105°F for medium-rare.
When you’ve hit the desired temperature, remove the package from the coals and let rest for about 10 to 20 minutes to let the roast come to serving temperature. Use your thermometer again, looking for 120°F for rare or 130°F for medium-rare.
To serve, gather up your guests so they can watch the excitement. Use the blunt back side of a knife to crack the salt crust in multiple spots. Remove any large chunks, then scrape away any remaining salt. Cut into thick slices.
Plate the slices of tenderloin with Colombian-style salted potatoes (recipe available here on Serious Eats) and top with your favorite chimichurri sauce.
A simple, but amazingly delicious dish!
Kenji displaying the finished plate.
J. Kenji López-Alt is the Managing Culinary Director of Serious Eats, and author of the James Beard Award-nominated column The Food Lab. If you love food and you don’t know Kenji, then you need to go introduce yourself! At the International Association of Culinary Professionals convention, where we took these photos, Kenji’s New York Times best-selling cookbook The Food Lab: Better Home Cooking Through Science, won awards for the Best American Cookbook and Best Overall Cookbook of 2015. You can order your very own copy here.