Preheat the oven to 250 degrees F.
Remove the tough lower stems of the kale. Toss the kale generously with olive oil, salt and crushed red pepper.
Lay the dressed leaves in a single layer on a sheet tray (use more than one if you need to!) and place in the oven. Roast the kale or until the leaves are crispy, 30 to 35 minutes.
Serve as a snack or side dish.