Preheat oven to 375°. Scrub potatoes; cute into small cubes. Brush with oil; sprinkle with 1/2 teaspoon salt and 1/4 teaspoon pepper.
Place in a foil-lined 15x10x1-in. baking pan; roast 30-45 min or until tender. Cool slightly. Place into a sprayed 9 x 13 inch casserole pan.
In a small saucepan, melt butter over medium heat. Whisk in whipping cream and 1/4 cup sour cream. Add 1-1/2 cups cheese; stir until melted. Remove from heat; Ppour over potatoes Sprinkle potatoes with remaining cheese and bacon.
Bake 30-35 minutes or until heated through. Sprinkle with remaining green onion. If desired, serve with additional sour cream. Yield: 8 servings.