Lay the leg portions on a platter, skin side down. Sprinkle with 1 tablespoon of the kosher salt and the black pepper. Place the garlic cloves, bay leaves, and sprigs of thyme on each of 2 leg portions. Lay the remaining 2 leg portions, flesh to flesh, on top. Put the reserved fat from the ducks in the bottom of a glass or plastic container. Top with the sandwiched leg portions. Sprinkle with the remaining 1/8 teaspoon kosher salt. Cover and refrigerate for at least 12 hours and up to 24 hours.

Preheat the water bath to 180ºF/ 82°C.

Remove the duck from the refrigerator. Remove the garlic, bay leaves, thyme, and duck fat and reserve. Rinse the duck with cool water, rubbing off some of the salt and pepper. Pat dry with paper towels.

Put the reserved garlic, bay leaves, thyme, and duck fat in a vacuum pouch along with the duck legs, making sure to keep the duck legs in one layer. Seal the bag and transfer it to the water bath. Cook the legs for 8 hours and up to 12 hours. The longer the duck cooks the more tender the legs will be. Once cooked transfer the pouch to an ice water bath and cool for at least 1 hour and up to 3 weeks.

To finish the ducks, remove the legs from the vacuum bag and pat dry. Heat a medium size saute pan over medium heat. Place the legs, skin side down, in the pan and cook until the skin is brown and crisp, about 2 to 3 minutes. Turn the legs over, reduce the heat to medium-low and continue to cook for 2 or 3 minutes longer until they are completely heated through.

Serve with the Beluga Lentil Salad.