Preheat the oven to 450℉.
In a small bowl, combine garlic, soy sauce, salt, pepper, thyme, rosemary, olive oil, and mustard.
Rub seasoning mixture on all sides of the pork roast.
Place a rack inside a roasting pan and place roast covered in rub on top of the rack.
Cook uncovered roast in preheated oven for 20-25 minutes or until the top starts to slightly brown.
Remove roast from oven and lower heat to 240℉.
Pour chicken broth and liquid smoke over roast and add vegetables on top and around roast.
Make a tent out of aluminum foil to put over the roast and return to the oven. Let the pork cook for 2 hours uninterrupted, but then start checking every hour or so and baste the roast with liquids from the bottom of the pan. Add more chicken broth to the pan if needed (you want liquid in the bottom the whole time so that the roast doesn't dry out).
The cook time will vary based on the size of your roast and your oven, so that's why it's recommended to start checking and basting your roast hourly. As a guideline, here are some cooking times:4 lb roast: 3.5 – 5 hours5 lb roast: 4 – 5.5 hours6 lb roast: 4.5 – 6 hours
The roast is done cooking when the internal temperature somewhere between 175-180℉.
Remove the roast from the oven, but keep the aluminum foil tent on top and let the roast rest for 15-20 minutes.
Slice or shred the pork (it should almost be falling apart at this point) and then drizzle with some of the pan juices.