Preheat your oven to 425 degrees F.
Rub 3 tablespoons of the honey dijon mustard on the chicken thighs. Season with salt and black pepper. Set aside.
In a medium bowl, whisk together the remaining honey dijon mustard, chicken broth, whole grain mustard, honey, thyme, and salt and black pepper to taste. Set aside.
Heat the olive oil in a large non-stick, oven-proof skillet over medium high heat. Add the chicken, skin side down. Sear for about 4 minutes until brown and then flip the chicken and sear for another 2 minutes. Pour the mustard mixture into the pan, and transfer it to the oven. Roast for 20-25 minutes or until the chicken has cooked through and reached an internal temperature of 175 degrees F.
Serve immediately, drizzled with creamy mustard sauce with a side of greens or fresh pasta.