Peel potatoes; cut into chunks. Cover with 1 inch of water in large saucepan or soup pot. Cover pan; bring to a boil. Reduce heat to a simmer. Cook potatoes until a knife tip easily penetrates a chunk of potato. Drain well. Return potatoes to hot pan to dry for a moment.
Add butter to potatoes. Partially mash potatoes with potato masher. Add 1/2 cup Marie’s Chunky Blue Cheese Dressing and continue to mash potatoes, adding more dressing as needed for desired consistency. Season to taste with salt and pepper. Spoon additional Marie’s Chunky Blue Cheese Dressing over each serving. Sprinkle with chives and serve hot.