Coat a large saute pan with olive oil and add the garlic cloves and crushed red pepper. Bring the pan to a medium heat and cook the garlic until it gets golden and very aromatic. Remove the garlic and discard.
Add the 2 types of kale and stir to coat with the oil. Season with salt and add the chicken stock. Cover and cook for 2 to 3 minutes.
Uncover and stir to be sure that the kale is cooked evenly. Let the liquid evaporate. Sprinkle with sherry vinegar. Taste to make sure that the kale is seasoned perfectly.
Recipe courtesy of Anne Burrell