For the smoothest mashed potatoes peel the potatoes, if desired skins may be left on. Cut potatoes into large pieces and place potatoes into a pot large enough to hold the potatoes. Cover with cool water, add salt to taste. Cook potatoes over medium-high heat in boiling salted water for 15 to 20 minutes, or until potatoes are tender. Drain potatoes. Mash in a large mixing bowl until no lumps remain. Add Marie’s® Chunky Blue Cheese Dressing and mix well. Add Gold-n-Soft® Margarine, salt, and pepper, and beat until mashed potatoes are light and fluffy.