Preheat oven to 300°F.
Trim the stem ends of the kale leaves and cut out any large ribs from the center of the leaves.
Rinse the leaves and pat them thoroughly dry. You can leave small leaves whole, but you may want to cut larger leaves into more manageable pieces.
Put kale in a very large bowl and drizzle with the oil. Gently toss the kale until evenly coated with the oil.
Arrange leaves on baking sheets in a single layer (you may need to cook them in batches). Sprinkle the kale with salt.
Bake for 20 minutes, remove, and let cool. The kale “chips” will crisp up as they cool. Repeat with remaining kale, if necessary.
Note: The key to successful kale chips is twofold: first, bake them in a single layer so they can crisp up properly and second, take them out of the oven after 20 minutes – they will crisp up as they cool. If you leave them in until they are crisp, they will char and take on a burnt taste.