Wash guinea fowl thoroughly in cold water and pat dry with a paper towel.
Guinea fowl should always be cooked until well done. To check visually to see if guinea fowl is done, pierce it with a fork. You should be able to insert the fork with ease, and wiggle the leg with ease. Guinea fowl dries out quickly; do not overcook.
Mix together 1 teaspoon salt and 1/4 teaspoon pepper; sprinkle over outside of whole guinea fowl and inside body cavity. Place guinea fowl in shallow pan, breast side up. Roast in 350F (180C) oven for 1 hour or until internal temperature reaches 180F (82.2C), basting occasionally. Let stand 10 minutes before carving.
Heat a skillet over medium heat. Add oil, then brown guinea fowls on all sides. Add cooking liquid (water, broth, or wine), herbs, spices, and vegetables, cover, and place in a 375F (190C) oven for 45 minutes or until done.
Heat skillet over medium heat. Rub guinea fowl with salt, pepper, and spices if desired. Add oil to skillet, then cook bird in covered skillet for 20 minutes. Uncover and cook another 10 minutes.
Rub guinea fowl with mixture of oil, salt, pepper, and spices. Place guinea fowl on prepared grill with rack about 8 inches (about 20cm) from heat source. Grill, turning frequently (using tongs to prevent piercing skin) until fork tender.
To test the temperature, place your palms above the coals or heat source at cooking level. If you have to remove your hands after 2 seconds, the temperature is hot; after 3 seconds, medium hot; and after 4 seconds, medium. More than 4 seconds indicates the grill has not reached cooking temperature.
Arrange guinea fowls in a shallow microwave dish. Cover and microwave on medium for 15 to 18 minutes.