In a large skillet, over medium-high heat melt the butter. Add the sliced onions and honey to the skillet and cook until the onions are tender and begin to caramelize, about 10 minutes. Stirring periodically.
Add the beef broth and bring it to a boil. Reduce the heat to low and add in the flour. Whisk continuously to incorporate well, and avoid leaving any flour chunks behind.
Continue to cook the mixture on low heat until it reduces. Add the seasonings, Dijon mustard, and Worcestershire sauce. Whisk well and continue reducing the gravy until it is the desired consistency.
Serve over mashed potatoes or with your favorite beef entree!