If starting with raw potatoes, preheat your oven to 400°F (200°C). Scrub potatoes clean, prick several times with a fork, and bake directly on the oven rack for 45-60 minutes until tender. Let cool, then cut into 1/2-inch cubes, leaving the skin on.
In a large Dutch oven or heavy-bottomed pot, cook the chopped bacon over medium heat until crispy, about 5-7 minutes. Remove bacon with a slotted spoon and set aside on paper towels, leaving about 3 tablespoons of bacon fat in the pot.
Add the diced onion to the bacon fat and sauté until translucent, about 4 minutes. Add the minced garlic and cook for another 30 seconds until fragrant.
Sprinkle the flour over the onion mixture and stir constantly for 1-2 minutes to cook out the raw flour taste.
Gradually whisk in the chicken broth, ensuring no lumps remain. Add milk, heavy cream, thyme, and smoked paprika. Season with salt and pepper to taste. Bring the mixture to a gentle simmer, being careful not to boil.
Gently fold in the cubed baked potatoes and continue to simmer for 10-15 minutes, allowing the flavors to meld. For a thicker consistency, mash some of the potato cubes against the side of the pot.
Stir in the shredded cheddar cheese until completely melted and incorporated.
Just before serving, stir in half of the cooked bacon and most of the green onions, reserving some for garnish. Taste and adjust seasonings as needed.
Serve hot with a dollop of sour cream, remaining bacon bits, green onions, and additional shredded cheese as garnish.