Rinse and pat the chicken dry with paper towels. Rub it with the salt and place it in a baking dish just large enough to hold it. In a blender or a food processor, combine the orange juice, olive oil, brown sugar, and shallots. Process until the shallots are finely minced. Pour the orange juice mixture over the chicken, crumble the bay leaf over the top, and cover the whole dish tightly with plastic wrap. Marinate in the refrigerator for at least 3 hours, preferably overnight, spooning the marinade over the chicken occasionally. Preheat the oven to 375 degrees. Transfer the chicken to a rack in a roasting pan, breast side down and reserve the marinade and add 1/2 cup water. Roast the chicken for 40 minutes, then turn to the other side and roast for 40 minutes more. As soon as you put the chicken in to roast, prepare the papaya glaze: strain the orange juice marinade into a food processor, discarding the solids, and add the mustard, garlic, halved papaya, thyme, salt, and pepper. Process the mixture for 10 to 20 seconds, scraping down the sides of the bowl as necessary, until smooth. Divide the glaze into halves and use half of it to baste the chicken as it roasts, basting thoroughly every 20 minutes or so. When the chicken is cooked through with no trace of pink remaining, remove it to a warmed serving platter and set aside at the back of the stove. Discard all the fat from the roasting pan, saving the pan drippings. Scrape the drippings into a small saucepan and place it over medium heat. Whisk in the butter, then add the remaining half of the papaya glaze and simmer the sauce for 4 minutes.
Garnish the platter with the parsley and watercress sprigs and the remaining half papaya, cut into long strips. Drizzle a little of the sauce over the top. Serve at once, passing the remaining sauce.
c.1997, M.S. Milliken & S. Feniger, all rights reserved