Prepared in 40 minutes or less.
In a medium pot, place the potatoes and cover them by 2 inches with salted water. Bring to a boil over medium-high heat and cook until potatoes are tender, approximately 30 minutes.
In the meantime, heat 3 tablespoons of butter in a skillet over medium-high heat. Add the kale leaves, carrots and onions. Cook until vegetables are soft, approximately 8-10 minutes. Season to taste and set aside.
Drain then peel cooked potatoes. Return them to the cleaned pot. Mash potatoes with a sturdy fork. Add milk, remaining butter, cooked vegetables and mix until butter is completely melted and the mixture is light and fluffy. Re-season to taste. Serve hot. Serves 4.