Choose an appropriately-sized pot for the amount of potatoes you are cooking. Place the prepared potatoes in the pot and cover completely with water. There should be space left at the top of the pot for the bubbling up of the potatoes as they cook. Place the pot of potatoes over high heat and bring to a full rolling boil. Reduce heat and cook potatoes for about 20 minutes, or until they are tender when pierced with a fork. Immediately remove the pot from heat, pour the potatoes through a colander to drain the water (completely) into a sink. Return the potatoes from the colander back to their original pot. Add salt, to taste, and 1/2 stick of softened butter or margarine. Whip the potatoes with an electric mixer until all lumps are gone. Now add 1/2 cup milk (more or less, depending on the amount of potatoes). Beat thoroughly, until the potatoes are light and fluffy. Add 1 cup of finely shredded blended Cheddar and Monterey Jack cheese and 2 tablespoons of fresh snipped chives. Use a large spoon and fold the cheese and chives into the whipped potatoes. You may fold until the cheese is completely melted, or leave streaks of cheese running through the potatoes. With a large spoon, spoon out the finished potatoes into a nice serving dish. Garnish with a few small pieces of fresh chives, if desired. This dish looks and tastes luscious!