01 - Preheat oven to 400°F. Grease a baking dish large enough to hold chicken in single layer.
02 - Whisk together Dijon mustard, whole grain mustard, honey, olive oil, lemon juice, garlic, smoked paprika, thyme, salt, and pepper until smooth.
03 - Place chicken breasts in prepared dish. Pour sauce over chicken, turning each breast to coat thoroughly.
04 - Bake uncovered for 30–35 minutes until internal temperature reaches 165°F and sauce is bubbling and caramelized.
05 - Broil on high for 2–3 minutes for golden color, watching carefully to prevent burning.
06 - Let rest 5 minutes. Spoon sauce over chicken and garnish with fresh parsley before serving.