Spray a 7qt crock pot with cooking spray.
Mix together the sour cream, cream of mushroom soup, green pepper, red onion, bacon bits, salt, pepper, and garlic powder.
Mix in 2 cups of cheese.
Fill the crock pot about 1/2 full with shredded potatoes.
Add to the crock pot a little over 1/3 of the wet mixture. Stir into the potatoes.
Top with 1 cup of cheese.
Fill the crock pot to the top with the remaining potatoes. Fill to the top - they will shrink down as they cook. Add in another 1/3 of the wet mixture and stir into the potatoes.
Top the potatoes with the remaining wet mixture.
Top with the remaining 1 cup of cheese.
Cook on low for 6 hours.