Heat the oil in a skillet or large pot and add the garlic and red pepper flakes. Cook over medium heat for 1 to 2 minutes or until the garlic begins to brown, stirring frequently.
Add the kale in batches, stirring after each addition so that it starts to wilt until all of the kale is added.
Season with salt and pepper, stir, and cook over medium heat for about 5 minutes or until the kale is just tender, stirring occasionally.