Preheat oven to 400°F. Grease a 2-qt. rectangular baking dish and set it aside.

Line a shallow baking pan with foil. Place a wire rack in the prepared shallow baking pan.

Arrange bacon slices on the wire rack in the shallow baking pan. Bake for 18 to 21 minutes or until crisp. Reduce oven temperature to 325°F. When cool enough to handle, crumble bacon.

In a large bowl, stir together mayonnaise, sour cream, green onions, garlic powder, and salt. Stir in bacon, potatoes, and cheese. Transfer to prepared rectangular baking dish.

Bake, uncovered, for 1 hour or until top and sides are browned and potatoes are tender.