Preheat the oven to 400 degrees. Line a baking sheet with parchment paper and set aside.
Scrub the potatoes and place them whole on the baking sheet. Use a fork to poke holes in the top of each potato. Bake for 1 hour until tender and cooked through.
Remove from the oven and allow to cool. Once cooled, slice in half the long way then use a spoon to scoop out the flesh and place in a large mixing bowl. Place the skins back on the baking sheet.
Add the sour cream, butter, cream cheese, milk, salt, pepper and thyme to the mixing bowl. Mash the potatoes with the rest of the ingredients until everything is well combined. Fold in the cheddar cheese.
Fill the potato skins with the mashed potato mixture until there is none left. Top with additional shredded cheese if desired.
Reduce the oven to 350 degrees and cook the potatoes for 20 minutes. Remove from the oven and serve. Top with bacon bits and green onions if desired.