Preheat oven to 300 degrees F. In a medium bowl combine 2 Tbsp. cider vinegar and 1 tsp. olive oil. Add 1 1/2 cups torn fresh kale (2- to 3-inch pieces), stems removed; toss to coat. Arrange kale pieces in a single layer on a very large parchment-lined baking sheet. Sprinkle with 1/8 tsp. sea salt. Bake for 20 minutes. Remove parchment with the kale from baking sheet. Let cool for 30 minutes.