Start by patting the chicken thighs completely dry with a paper towel. This helps the skin crisp up better when it hits the hot skillet later. In a small bowl, mix the garlic powder, paprika, onion powder, salt, and Italian seasoning, then rub it generously all over the chicken.
Heat the olive oil in a large skillet over medium-high heat until it's shimmering. Place the chicken skin side down and let it cook for 4-5 minutes until the skin turns golden and crispy. This step locks in flavor and gives the chicken a much better texture later.
Once the skin is crispy, use tongs to move the chicken into your slow cooker, arranging it skin side up in a single layer. This keeps the crispy skin from getting soggy as it cooks. Try not to overcrowd the pieces so they cook evenly.
Pour the chicken broth around the chicken, then scatter the diced butter and minced garlic on top. These ingredients create a rich, savory liquid that slowly infuses into the meat as it cooks. This is really where all the magic happens.
Cover the slow cooker with its lid and set it to LOW for about 4.5 to 5 hours. Cooking it low and slow is what makes the chicken so tender that it falls right off the bone. Resist the urge to lift the lid too often, since this lets heat escape and extends the cooking time.
Before removing the chicken, check that the internal temperature has reached 165°F using a meat thermometer. Once it's ready, garnish with fresh parsley for a pop of color. Spoon some of the cooking juices over the top for extra flavor.