Preheat the oven to 400°F (200°C). Place a rack in the middle.

Pat the chicken very dry with paper towels. Season both sides with kosher salt and black pepper.

Heat an oven-safe skillet over medium-high heat. Add 2 tablespoons butter and 2 tablespoons olive oil.

When the fat is shimmering, add the thighs skin-side down. Sear without moving for 6 to 8 minutes until the skin is deeply golden and crisp.

Flip the thighs and cook 1 to 2 minutes on the meat side, then transfer them to a plate.

Lower the heat to medium. Add the remaining butter and let it melt. Add the minced garlic, paprika, Italian seasoning, and red pepper flakes. Sauté briefly until fragrant, about 30 seconds to 1 minute.

Stir in the grated Parmesan so it melts slightly into the butter-garlic mixture. Turn off the heat.

Return the thighs to the skillet, skin-side up. Spoon some sauce over each piece so flavors cling to the meat.

Transfer the skillet to the preheated oven.

Bake for 15 to 20 minutes, until an instant-read thermometer inserted into the thickest part reads 165°F (74°C).

If you want a more browned top, broil on high for 1 to 2 minutes, watching closely to prevent burning.

Remove from the oven and let the chicken rest for 5 minutes. Sprinkle with chopped parsley before serving.