4 6-oz, 1 1/2-inch-thick, skin-on, scaled salmon fillets
2 tablespoons olive oil
1 teaspoon kosher salt
1 teaspoon ground black pepper
1 tablespoon minced tarragon
1 shallot, minced
1 vacuum seal bag
3 tablespoons grapeseed oil
1 tablespoon garlic and herb butter
DirectionsFill 8-quart stockpot with 6-quarts hot tap water. Set immersion circulator into water bath and attach to side of pot. Set circulator to 140˚F.
Add salmon, olive oil, salt, pepper, tarragon and shallots to a medium mixing bowl. Toss gently to coat. Fold top 2-inches of a 1-quart vacuum seal bag over to form a collar. Add salmon and marinade to bag. Using vacuum sealer, create a seal and remove air from packaging.
Confirm immersion circulator has heated water to 140°F by using a calibrated digital probe thermometer. Place sealed bag directly into circulating water bath and cook for 1 1/2 hours.
Remove bag, and using a calibrated digital probe thermometer inserted into the thickest fillet, confirm internal temperature has reached at least 145°F. Remove salmon from bag, blot dry.
Heat oil in a cast iron skillet over medium heat for 4 minutes. Add salmon skin-side down and butter to the pan. Sear 3 minutes until crispy and the butter begins to brown. Spoon brown butter over salmon while searing. Squeeze lemon over salmon, season with salt and pepper, flip over and sear for an additional 30 seconds while spooning pan sauce over top. Season with salt and pepper.