Preheat the oven to 375 degrees F.

Place the chickens on a flat work surface and using kitchen shears, cut away and remove the backbones. With a sharp knife, cut each bird in half through the center of the breast. Remove the breast and rib bones. Cut away the outer 2/3 of the wing bone, leaving the last joint intact. Cut into and remove the thighbone. Repeat with the remaining chicken and reserve the bones for another use.

Plating 1: Season the chickens on both sides with the Essence. Heat 1 tablespoon of the oil in each of 2 skillets over medium-high heat. Place 2 chicken halves, skin side up, in each hot pan and sear on 1 side for 6 minutes. Remove from the heat. Add 2 tablespoons of the butter and 4 sprigs of thyme to each pan. Place in the oven and roast for 16 minutes on the same side. Remove from the oven and carefully turn the chicken halves with tongs. Spoon pan juices over the skin side of each chicken and roast until the skin is crisp and the chickens are cooked through, about 10 minutes.

Remove from the oven and place the chicken halves on a cutting board. Carefully cut away the breast from each half and carve into 5 slices.

Arrange the sliced breast along the top of a plate and place the leg to the side. Spoon the sauce over the chickens and arrange the mushrooms to the side. Garnish each plate with watercress and 4 sprigs of thyme and serve.

Plating 2: Preheat the oven to 375 degrees F.

Place the chickens on a flat work surface and using kitchen shears, cut away and remove the backbones. With a sharp knife, cut each bird in half through the center of the breast. Remove the breast and rib bones. Cut away the outer 2/3 of the wing bone, leaving the last joint intact. Cut into and remove the thighbone. Repeat with the remaining chicken and reserve the bones for another use. Lightly pound out the chicken halves between 2 sheets of plastic to flatten. Season the inside of the chicken with salt and pepper.

Have the sauteed mushrooms, cooled, in a bowl. Place the mushrooms on the chicken and roll up, lengthwise, around the filling. Tie the roll at 1-inch intervals. Place the chicken roll in a hot pan and sear on all sides for 6 minutes.

Remove from the heat. Add 2 tablespoons of the butter and 2 sprigs of thyme to each pan. Place in the oven and roast for 16 minutes on the same side. Remove from the oven and carefully turn the chicken halves with tongs. Spoon pan juices over the skin side of each chicken and roast until the skin is crisp and the chickens are cooked through, about 10 minutes. Remove and let rest on a cutting board for 5 minutes before slicing.

Slice the chicken roulade and put the slices on a platter. Spoon the sauce around the roulade and plate with watercress.