1 tablespoon olive oil
1 white onion, sliced
2 Pink Lady apples, cored and cut into bite-sized pieces
2 teaspoons apple cider vinegar
1/8 teaspoon salt
1/8 teaspoon pepper
4 cups kale, center ribs removed and chopped
Heat olive oil in a large skillet over medium heat; cook and stir onion until tender, about 4 minutes.
Add apples, vinegar, salt, and pepper; cover skillet and cook until apples are tender, about 3 minutes.
Add kale; cover and cook until kale is tender, 4 to 5 minutes.