Heat oil in large skillet over medium-high heat. Season chicken on both sides with salt and pepper. Add chicken to skillet; cook for about 5 to 6 minutes per side or until internal temperature reaches 170°F on an instant-read thermometer when inserted into chicken. Remove to platter and keep warm.
Add broth, capers, rosemary and thyme to skillet; cook over medium-high heat, scraping up any browned bits from bottom of skillet, for 5 minutes. Remove skillet from heat; stir in the mustard, butter and honey just until the butter is incorporated; butter should not completely melt and sauce should be frothy and somewhat thick. Pour sauce over chicken. Serve immediately with couscous, if desired.