Separate and trim cabbage leaves. Bring a large pot of water to a boil and add cabbage and cook for 5-10 min. or until tender. Drain and chop coarsely. Set aside.
Boil potatoes in a large pot of boiling water until tender. Mash with milk, margarine, and pepper to taste.
Preheat oven to 350F. Meanwhile to make the cream sauce, in a medium saucepan melt the margarine and add the onion and cook until translucent.
Stir in the flour and cook for 1 min. Add the milk slowly and cook stirring for 3-5 min. until the mixture comes up to a simmer and thickens. Season with salt, pepper, and nutmeg to taste. Mix in cabbage.
Spoon the cabbage into a 4 cup baking dish that is non-stick or spray lightly with cooking spray.
Cover with the mashed potatoes and sprinkle with paprika. Bake for 20-30 min. or until heated through. Lightly brown under the broiler before serving.