Place potatoes into a medium-sized pot. Add enough water to cover the potatoes. Place the pot on the stove, turn the burner on high, once the potatoes boil turns down the temperature to medium. Cook the potatoes for 15 to 20 minutes or until the potatoes are tender when pierced with a fork. D
Drain potatoes and return to the pot. Add heavy cream, butter, salt, and pepper.
Add green onions, and stir them in with a spoon.
Place potatoes into a serving dish, make a well in the mashed potatoes. Add the butter to the well in the mashed potatoes. Serve once the butter has melted.
Russet potatoes are my first choice for this recipe. But if you can't find Russet potatoes, you can use Yukon Gold or even red potatoes for this recipe.
You can either mash the potatoes manually with a potato masher, or you can use an electric mixer. Do not blend the potatoes past once they have become smooth. Over blending may make for gummy mashed potatoes.
If you can help it, do not substitute the butter for margarine. Butter may cost a little more, but the flavor is much better with butter.
I also recommend using heavy cream in this recipe for the creamiest mashed potatoes. The flavor is rich, but it will also help those mashed potatoes reheat should you need to do that. I personally think these mashed potatoes would make some killer potato pancakes.