Preheat the oven to 100ºC and prepare two large baking trays.
Destem the kale, and tear into chunks. Rinse the leaves and dry thoroughly in a salad spinner (the dryer they are, the crisper they'll turn out).
In a large bowl, drizzle the oil over the kale leaves, and massage it in so that all the leaves are coated.
Sprinkle the salt, nutritional yeast and paprika onto the kale and mix thoroughly.
Spread the kale evenly between the two baking trays, and pop them in the oven. Bake for about 30 minutes, checking halfway to stir and redistribute the leaves so they dry evenly.
Remove when crispy, and let cool completely before storing in an airtight container (if you haven't already polished them off).