Cook's Illustrated. Here are their notes: For pork tenderloin that was perfectly tender and juicy from edge to edge, we used an immersion circulator. We began by lightly pounding the pork to create two flat sides that would be easy to sear. Halving the tenderloins crosswise created moderately sized steaks that were easy to maneuver. We placed the pork and a bit of vegetable oil in a plastic bag, making sure to remove as much air as possible to ensure even cooking. Submerged in a 140-degree water bath, the pork was guaranteed to remain moist and tender and to cook evenly from edge to edge. For great browning, we made sure to pat the pork very dry before searing it in a hot skillet.
Ingredients
2 (1 lb) pork tenderloins, trimmed
Salt and pepper
1/4 cup vegetable oil
Scallion-Ginger Relish
Instructions
1. Using sous vide circulator, bring 4 quarts water (water should be 4 inches deep) to 140°F/60°C in 7-quart Dutch oven or similar-size heatproof container.
2. Pound tenderloins to 1-inch thickness. Halve each tenderloin crosswise to create 4 steaks total. Sprinkle each steak with 1/2 teaspoon salt and 1/2 teaspoon pepper. Place steaks and 2 tablespoons oil in 1-gallon zipper-lock freezer bag. Seal bag, pressing out as much air as possible. Gently lower bag into prepared water bath until pork is fully submerged, then clip top corner of bag to side of pot, allowing remaining air bubbles to rise to top of bag. Open 1 corner of zipper, release air bubbles, and reseal bag. Cover pot with plastic wrap and cook steaks for at least 1 hour or up to 2 hours.
3. Line wire rack with double layer of paper towels and place in rimmed baking sheet. Transfer steaks to paper towels, cover with another double layer of paper towels, and let stand for 10 minutes.
4. Pat steaks until surfaces are very dry. Heat remaining 2 tablespoons oil in 12-inch skillet over medium-high heat until just smoking. Increase heat to high, place steaks in skillet, and sear until well browned on both sides, 1 to 2 minutes per side. Transfer to carving board and let stand for 5 minutes. Slice against grain ¾ inch thick and transfer to serving platter. Season with salt to taste. Serve with Scallion-Ginger relish.