Preheat the oven to 150C.
Wash the kale and dry thoroughly.
Shred the kale, discarding any tough stalks.
Spread the kale evenly over a large baking tray. Drizzle with the oil and toss to coat.
Sprinkle nutritional yeast over the top, if using, or season with salt if preferred.
Bake in the oven for 20-30 minutes, turning the kale over with a spatula 2 or 3 times.
When the kale is crispy and crunchy, remove from the oven. Leave to cool for a few minutes before serving.