Combine honey, mustard, garlic, orange juice, lemon juice, chili flakes, thyme, salt and pepper in a medium bowl, whisking to blend well.
Place the brisket in a resealable plastic bag. Add the marinade, seal, and refrigerate at least 1 hour, or up to 24 hours.
Remove brisket from refrigerator and allow to come to room temperature.
Preheat oven to 350°F.
Heat evoo in a Dutch oven over medium heat. Remove brisket from marinade (reserve marinade) and sear 5 minutes per side or until nicely browned.
Pour marinade from plastic bag over brisket, add 3 cups chicken broth, cover, and bake at 350°F for 3 hours or until tender.
Remove brisket to a cutting board and let rest at least 15 minutes before slicing against the grain.
Transfer braising liquid to an unheated saucepan. Skim off the fat. Reduce the liquid by boiling on medium-high, uncovered, until it coats the back of a spoon. Season with salt and pepper. Pour over sliced brisket and serve.
Notes
The brisket and marinade can be prepared up to 24 hours in advance before baking.