Prick each potato several times with a fork and season with salt and pepper. Wrap each potato in aluminum foil and place them in the crockpot.
Cook on low for 6-8 hours or on high for 4-5 hours, until the potatoes are tender.
Once cooked, carefully remove the potatoes from the crockpot and unwrap them. Cut each potato lengthwise and gently squeeze to open.
In a mixing bowl, combine the sour cream, garlic powder, onion powder, and milk (if using). Stir well to combine.
Spoon the sour cream mixture into each potato, then top with shredded cheddar cheese, crumbled bacon, and chopped green onions.
Return the loaded potatoes to the crockpot and cover. Cook on low for an additional 30 minutes to melt the cheese.
Serve warm and enjoy your delicious loaded potatoes!