While the sausages are cooking, heat the remaining schmalz in a large non-stick skillet over medium heat. Add the potatoes and cook, over high heat until the potatoes are golden brown; about 8-10 minutes. Season with salt and pepper.
NOTE: Remove the smoked streaky bacon piece from the pan with Grünkohl. Using a knife, separate the meat from the fat and mix it in with the kale. Discard the fat.