Green Mashed Potatoes

3/4 cup milk
4 thinly sliced scallions
4 cups thinly sliced kale
salt
white pepper
6 large Yukon gold potatoes, cooked, peeled, and mashed
3 tablespoons butter

In a large heavy saucepan bring the milk to a boil. Add the scallions, kale, salt and pepper and return to a boil. Reduce the heat and simmer until the kale is very tender and bright green, but not mushy. While the kale is cooking, whip the potatoes with the butter. Fold in the milk mixture and mix well to combine. Serve hot.