Preheat the oven to 225 degrees F.
Put the kale leaves in a bowl. Lightly pour the olive oil over the kale until the kale is glistening and coated; do not apply too much oil. Sprinkle the oregano and za'atar over the top of the kale. Season with salt and toss.
Transfer the kale to a baking sheet. Bake until crispy, 45 minutes to 1 hour, depending on your oven. Cool and serve.