Spray the bottom of the Crock Pot generously, then spread the frozen potatoes O’Brien across the base. The potatoes should form an even layer with no exposed dry patches of the insert.

Sprinkle one-quarter of the shredded cheese over the potatoes. This first cheese layer creates savory pockets between the potatoes and eggs as the scramble sets.

Whisk the eggs in a large bowl until the color is completely even, then whisk in the heavy cream and pour the mixture over the potatoes. The mixture should look smooth and lightly foamy, which helps create a softer, fluffier texture.

Scatter the remaining cheese over the top, leaving about 1/2 inch clear around the inside edge of the crock. Keeping that border bare helps the outer cheese avoid getting too dark before the center is done.

Cover and cook on low for 5 to 8 hours. Cooking time varies by slow cooker, so begin checking when the eggs look mostly set and the kitchen smells buttery and cheesy.

Turn off the heat when the top is lightly browned and the center no longer jiggles, then finish with the diced chives. A knife inserted near the center should come out without pooled liquid before you serve.