Although sold alongside peanuts, almonds and pistachios in the snack aisle, cashews technically are not nuts. Instead, they are the seeds found in cashew apples, a fruit that grows on trees in tropical climates. Cashew apples aren't common to the United States, but raw cashews are typically sold in health food stores and through online retailers. Although they can be eaten raw, roasting cashews enhances their flavor.
Preheat oven to 325 degrees Fahrenheit. Rinse the raw cashews under cool running water using a colander to remove any debris picked up during processing. Line the colander with several sheets of paper towels and shake the cashews dry.
Line a rimmed baking sheet aluminum foil or a silicone mat. Add the raw cashews to a bowl along with a small amount of vegetable oil. Toss the cashews in the oil, and then sprinkle liberally with salt. Toss the cashews again.
Lay the raw cashews on the baking sheet and spread them out into a single layer. Place the baking sheet into the oven and roast the cashews for 15 to 20 minutes, or until they begin to turn light brown. Monitor the roasting process closely, tossing the cashews occasionally with a long-handle spoon, so as to avoid burning them.
Remove the pan from the oven and allow the cashews to cool. Add more salt if desired.