*available at Asian markets, specialty foods shops, and some supermarkets **available at some butcher shops In a small bowl stir together the five-spice powder and 2 tablespoons of the oil, rub the mixture on the guinea hens, and season the hens with salt. In a large heavy skillet heat the remaining 2 tablespoons oil over moderately high heat until it is hot but not smoking and in it brown the hens lightly, 1 at a time. Arrange the browned hens, breast side down, in 2 roasting pans and roast them in a preheated 350F. oven, switching the pans from one rack to the other after 30 minutes, for 50 minutes to 1 hour, or until a meat thermometer inserted in the fleshy part of the thigh registers 170F. Transfer the hens to a cutting board and let them stand, covered loosely with foil, for 15 minutes. Make the sauce while the hens are standing: Skim the fat from the pan juices, divide the wine between the pans, and deglaze the pans over high heat, scraping up the brown bits. Transfer the mixture to a large saucepan, add the zest, the gingerroot, and the star anise, and boil the mixture until the liquid is reduced to about 1/3 cup. Add the broth, the water, and the soy sauce and cook the mixture at a slow boil for 5 minutes. Stir the cornstarch mixture, stir it into the zest mixture, and simmer the sauce for 2 minutes. Strain the sauce through a fine sieve into a saucepan and keep it warm. Carve the guinea hens, divide the broccoli rabe among 8 heated plates, and arrange the meat on it. Spoon some of the sauce over each serving and serve the remaining sauce separately. To make steamed broccoli rabe: Trim and discard any yellow or coarse leaves and the tough stem ends from the broccoli rabe and wash the broccoli rabe well in several changes of cold water. In a steamer set over boiling water steam the broccoli rabe, covered, for 4 to 5 minutes, or until the stems are tender. Serves 8. Gourmet October 1992