Pat chicken thighs completely dry with paper towels on both sides. Season skin and meat evenly with garlic powder, smoked paprika, salt, and black pepper.

Heat olive oil in a large 12-inch heavy cast-iron skillet over medium-high heat until shimmering.

Place chicken thighs skin-side down in skillet. Sear undisturbed for 7 to 9 minutes until skin is deeply golden, rendered, and shatteringly crisp. Flip and cook meat side for 4 to 5 minutes. Transfer chicken to a clean plate (it will finish cooking in glaze).

Drain excess chicken fat from skillet, leaving about 1 tablespoon of flavorful drippings.

Reduce heat to medium. Add minced garlic and cook for 1 minute until fragrant. Pour in chicken bone broth and apple cider vinegar, scraping up all browned fond from skillet bottom.

Whisk in pure honey, Dijon mustard, whole grain mustard, rosemary, and thyme sprigs. Bring to a gentle bubbling simmer for 3 minutes until sauce begins to gloss and reduce.

Swirl in 1 tablespoon of butter until velvety.

Nestle seared chicken thighs back into skillet skin-side up (avoid pouring sauce directly over crispy skin to keep it ultra-crunchy).

Simmer over medium-low heat for 6 to 8 minutes until chicken reaches an internal temperature of 175°F (80°C) and sauce is syrupy.

Spoon glossy honey mustard sauce around chicken thighs, garnish with fresh thyme leaves, and serve warm immediately.