In a large bowl, mix all the potatoes, oil, garlic powder, sea salt and pepper. Toss well to get them all coated.
Add half the potatoes to the slow cooker, then add in some tomatoes, half of the cheese, sprinkle with cooked, crumbled bacon and green onions.
Repeat, then sprinkle with chili slices.
Cover and cook on high until potatoes are fork tender, about 4-5 hours. (The cooking time depends on the size of the chopped potatoes).