Peel and slice potatoes length wise in quarters, then slice 1/4 " wide. (I used Costco® potatoes).
Boil for about 35-40 minutes or until potatoes are soft and tender.
Drain water, set aside.
Boil 8 eggs. Once done, rinse in cold water.
Once cool enough to handle, peel and chop eggs, set aside in a small bowl.
Preheat oven to 350°
In a large 9 x 13 baking dish, spray with cooking spray.
Add a layer of sliced potatoes to bottom of baking dish.
Top with 1/2 of the sliced butter.
Spoon a layer of chopped hard boil eggs on top of potatoes.
Sprinkle with 1/2 of the chopped onions.
Add 1/2 of the garlic.
Next, spread 1/2 of the sour cream.
Sprinkle with 1 cup grated cheese.
Then another layer of potatoes, butter, eggs, onions, garlic, sour cream.
Add salt and pepper.
Final layer is the remaining sliced potatoes, and grated cheese.
Cover with foil.
Cook for 60 -65 minutes.
Remove foil and continue cooking until cheese is browned a bit, approximately 10-15 minutes.