- Rinse the kale and roughly chop. Heat the olive oil in a large saucepan or skillet with a cover. Add the garlic and onion and cook until fragrant, about 5 minutes.
- Increase the heat to high; add the vegetable stock and chopped kale, tossing to coat. Cover and steam for about 5 minutes. Remove cover and continue cooking, stirring frequently, until all the liquid has evaporated.
- Season with salt, pepper and red wine vinegar and serve.