Garlic, crushed, about 3 cloves, as needed (for sous vide bag cook)
Fresh herbs, as needed (for sous vide bag cook)
1 Egg white
1.5-2 cups beef stock (for sauce)
Rub: 2 Tbsp. black pepper, 2 Tbsp. salt, 1 Tbsp. dried thyme or 2 tsp. fresh thyme, 1 Tbsp. dry mustard, zest of 2 lemons (tends to be a bit too salty, maybe half?)
Directions
Heat your sous vide to the desired doneness you wish to achieve:
Rare: 122 °F / 50 °C
Medium-rare: 129 °F / 54 °C
Medium: 136 °F / 58 °C
Medium-well: 144 °F / 62 °C
Well-done: 154 °F / 68 °C
Season your roast with salt and pepper, then heat a heavy pan over medium-high heat and add oil. When the pan is very hot, add the roast. Give it a good sear for about two minutes per side, but don’t bother searing the rib side. The goal is to build a good, dark crust. Remove the roast and set it aside.
Add garlic and any fresh herbs to the pan and toast them. When they are fragrant and toasty, scoop them onto the roast and allow the whole thing to cool for a few minutes. Place roast and herbs into sous vide bag, being careful of the bones.
Place sous vide bag into water and allow the roast to cook 4–6 hours. Thinner roasts will take toward the shorter end and thicker roasts toward the longer end of the range, but don’t stress – you can leave the meat in the water for a couple of extra hours.
An hour before you want to finish your meat, start working on the rub: beat egg white to a foam, and prepare rub.
Remove roast from the bag and transfer it to an oven-safe platter or baking tray. Save juices and other remnants to make sauce later.
Coat entire roast with egg white, avoiding the bone section. This steps helps the herb rub stick to the surface of the meat and develop a nice crust in the oven. Evenly sprinkle rub around the roast, coating as much of the meat’s surface as possible.
Heat a pan over medium-high heat. When the pan is hot, pour in the juices, garlic, and rosemary from the bag, and reduce the mixture until almost no liquid remains. Once the garlic and herbs start browning, add beef stock and let it simmer until it’s saucy and thick. Strain the sauce and add extra herb rub or seasonings of your choice. Remove from the heat and set aside for serving.
Heat the oven to 475 °F / 250 °C (with convection on if applicable). Roast the beef for about 5–15 minutes. Ovens vary, so just keep an eye on the meat and take it out when it looks right. If you have a thermocouple probe, stick it about a half-inch below the roast’s surface to monitor the temp.
Note
5-7 hours total cook time.
via Chef Steps. Instructions to French the roast can be found in the article link.