Serve with South Gate chef Kerry Heffernan's Corned Salmon with Braised Fingerling Potatoes.
Melt butter in a medium saucepan over medium heat; add leek and season with salt and pepper. Add 2 tablespoons water and cook until softened, about 2 minutes. Add cabbage and cardamom, if using, and season with salt and pepper. Continue cooking, stirring occasionally, until cabbage is just wilted. Remove from heat and serve.