Preheat the oven to 375°F (190°C).
In a large oven-safe skillet or casserole dish, cook the chopped bacon over medium heat until crispy, about 5-7 minutes. Remove bacon with a slotted spoon and set aside, leaving the bacon fat in the pan.
Pat the chicken thighs dry with paper towels. Season both sides of the chicken thighs with salt, black pepper, garlic powder, and smoked paprika.
Add the unsalted butter to the bacon fat in the skillet and melt over medium heat.
Place the seasoned chicken thighs skin-side down in the skillet. Sear for 5-6 minutes until the skin is golden brown and crispy. Flip the chicken and cook for an additional 3 minutes.
Sprinkle the cooked bacon evenly over the chicken thighs.
Sprinkle the shredded cheddar cheese and grated Parmesan cheese evenly over the top of the chicken and bacon.
Transfer the skillet or casserole dish to the preheated oven and bake for 25-30 minutes, or until the chicken is cooked through and the cheese is melted and bubbly.
Remove from the oven and let rest for 5 minutes before serving.