Season the chuck roast liberally with salt + pepper all over.
Poke holes in the roast and insert garlic slices into the holes. Rub with 1 Tbsp. oil.
Heat a large pot, over high heat (preferably a Dutch oven). Heat 1 Tbsp. oil. Sear the roast 3-4 minutes per side and then remove and set aside.
Sauté the onion for 3 minutes before adding the carrots and mushrooms and cooking 5 more minutes. Remove and set aside.
Add the balsamic vinegar and deglaze the pan, scraping up any cooked-on pieces from the pan.
Add the tomato paste, Worcestershire, thyme and cranberries and cook for 1-2 minutes, stirring until aromatic. Pour in broth and maple syrup and stir. Add the meat and veggies back in the pan and cover.
Let the roast come to a boil and then reduce to a low simmer. Let cook for 3-4 hours until meat is falling apart and tender. Cut away kitchen twine and place roast and vegetables on a serving plate.
To make a sauce, bring the remaining liquid to a low boil in the pan. Skim away any visible fat. Mix cornstarch with 1 Tbsp. cold water, stir into the sauce and bring to a low boil for 2-3 minutes. Serve with the meat and veggies over mashed potatoes, polenta or egg noodles.