In a mixing bowl, whisk together the sauce components: honey, chicken broth, dijon mustard, whole grain mustard, white vinegar, and sriracha. Set this prepared mixture aside.
In a separate small bowl, blend the paprika, ground mustard seed, cayenne, kosher salt, and black pepper. Use this dry seasoning mixture to thoroughly coat each chicken breast on all surfaces.
Warm a non-stick skillet over medium heat. Drizzle in half the olive oil and sear each seasoned chicken breast for approximately 2 minutes per side, just until lightly browned.
While searing, begin heating the oven to 375°F (190°C).
Transfer the seared chicken pieces into a baking dish suitable for the oven. Pour the honey mustard sauce evenly over the top of the chicken.
Place the baking dish in the preheated oven and cook for 15 to 25 minutes, depending on thickness, or until the internal temperature reaches 165°F (74°C).
Once baked through, remove from the oven. Sprinkle with fresh thyme just before serving.