Gather the ingredients and preheat your oven to 350°F (175°C).
Pat the pork butt roast dry and rub all sides with garlic powder, salt, and pepper.
Heat olive oil in a heavy skillet over medium-high. Sear the roast on all sides until golden brown, about 3 minutes per side.
Transfer roast to a large roasting pan. Surround with carrots, potatoes, onion, and mushrooms.
Scatter minced garlic, thyme, and rosemary over the vegetables. Pour chicken broth into the pan base.
Cover tightly with foil and roast for 3 hours. Uncover and roast an additional 1 hour until pork is tender and internal temperature reaches 195°F.
Remove from oven and let rest, covered, for 15–20 minutes.
Slice or shred the pork, serve atop the tender-roasted vegetables, and drizzle pan juices over the top.