To start, preheat the oven to 350. Tear up the kale leaves into large-ish bite-size pieces, keeping in mind that they'll shrink in the oven. Be sure to separate the stems and the central "rib" of each leaf and discard. Rinse leaves well and completely dry.
Put a piece of parchment paper on a baking sheet. (Depending on how much kale you have, you might need two sheets.) Arrange the kale leaves on the parchment, avoiding overlap as much as possible. Brush leaves with olive oil and sprinkle with desired seasonings. I did one batch with seasoned salt and grated parmesan cheese, and another batch with sea salt and rice vinegar. Bake in oven for 10-15 minutes, until leaves are crisp -- they should be browned but not burned.