Wash skins of potatoes, pierce skin by making 3-4 slits with a sharp knife; then place potatoes on a paper towel lined dish in the microwave. Microwave 5-10 minutes.

Allow to cool slightly, then remove the skins. I hold them with a paper towel so I don't burn my hands.

Dice the potatoes into ½" pieces and set aside.

In a large pot add the butter, onions and scallions and saute until the onions start to soften.

Add in the flour to form a roux; then gradually add in the vegetable broth.

Heat the milk to temper it, then add it to the pot along with the cooked potatoes, pepper and salt.

Allow the soup to simmer for 20 minutes, then combine the cornstarch and water; add it to the pot and mix well until soup has thickened.

Pour soup into serving bowl and garnish with cheese.