Add the potatoes, onion, kale, a bay leaf, a pinch of salt and just enough water to cover all in a 3 qtrs. pan. Cover and boil gently for about 25 minutes. Meanwhile steam the smoked sausage for the same amount of time and slice. Remove the bay leaf, drain the vegetables, and mash them.
Add milk and butter. Stir in the hot, sliced smoked sausage, add salt and pepper to taste and serve.