Prepare the vegetables as directed above. Melt the margarine in a deep skillet. Let the margarine heat up, and then add 3 chopped potatoes, 1 chopped carrot, and 1 chopped onion. Salt to taste (about 1 teaspoon). Sir the salted vegetables around in the skillet to coat them with the melted margarine. After they sizzle a bit, turn the heat to a fairly low temperature, cover with a lid, and let them cook until soft. Stir occasionally while the vegetables cook. If they brown a bit, that's fine--it just adds to the flavor. However, you do not want to let them burn. When the vegetables are done, mash them a bit with a potato masher (or spoon). They will look like "smashed potatoes." You will want to leave a few lumps. Now, remove them from heat and add 2 cups of milk. Stir around gently until you have soup of a nice consistency. You may heat the soup back up to boiling, but do not continue to boil it. It is not necessary to heat it, because it will still be very hot after the addition of the milk. Pour the soup into a soup tureen and use kitchen shears to mince some fresh parsley over the top. Terrific, hearty, lovely soup!