Place the potatoes in a large pot and add water to cover to the top, minus 2 inches. Add 2 teaspoons of salt and cover with a lid. Bring to a boil, reduce the heat to LOW and simmer with the lid slightly off until the potatoes are soft, about 20 minutes. TIP: Pierce the potatoes with a fork to see if they are done.
In a skillet over medium heat at the oil and when hot, add the shallots. Fry the shallots until they are a dark brown in color, about 4 minutes. Set aside.
In a small saucepan, combine the milk and the butter and heat on LOW until the butter is melted. Set aside.
Once the potatoes are done, drain them well and transfer back into the large pot. Using a potato masher, lightly mash the potatoes to break them up. Next, add the milk and butter mixture and the sour cream. Continue to mash until combined. The mixture will be lumpy!
Lastly, stir in the browned shallots along with the oil from the pan and season to taste with salt and pepper.
Lightly sprinkle with a tiny bit of fresh chopped parsley.
Add a slab of butter to the hot potatoes and allow it to slightly melt.