Dead simple ...
Take all the stalky bits of the kale, spread it out on an ovenproof tray, drizzle of olive oil and some sea salt.
Into the oven at 200C for 10-15 minutes, keeping an eye on it and retrieving it once it has gone crisp, but before it really starts to brown.
Cool!
Great as part of a meal and fun to just eat while watching a film, or something.
Have fun ...