Raw peanuts can be oven-roasted, microwave-roasted or oil-roasted. Peanuts prepared in the oven can be shelled or left in the shell. However, peanuts need to be shelled when using other cooking methods.
Place peanuts single-layered in a shallow baking pan. Roast shelled peanuts for 15 to 20 minutes and peanuts in the shell for 20 to 25 minutes. Season peanuts after they are removed from the oven. When microwaving peanuts, place 1 cup of shelled peanuts that have been moistened and seasoned with salt into a small, microwave-safe plate. In a 700-watt oven, cook on high for 2 1/2 minutes, stir, and cook for another 2 1/2 minutes.
To oil-roast peanuts, heat peanut oil to 350 degrees Fahrenheit in an electric skillet or heavy saucepan, add 2 cups of peanuts, and cook for approximately five minutes, stirring occasionally.