Season the chicken with salt and pepper. Heat olive oil and butter in a large skillet over medium-high heat. Add chicken and cook for 5 minutes per side. Add 1/2 cup of chicken broth, cover, and cook for another 5 to 6 minutes. Remove chicken from skillet. Add onion to skillet and cook for 3 to 4 minutes to soften. Add remaining chicken broth and simmer for 2 minutes. Stir in creole mustard, honey, heavy cream, and cayenne pepper. Simmer for 3 to 4 minutes to thicken the sauce. Return chicken to skillet. Cook for a minute or two to warm the chicken. Sprinkle thyme over chicken. Check sauce for seasoning and add salt and pepper if needed. Serve.
