1. Pat the 3-pound chuck roast dry with paper towels and season all sides with salt, pepper, garlic powder, and onion powder.
2. Heat 2 tablespoons of olive oil in a large skillet over medium-high heat. Brown the roast on all sides, about 4-5 minutes per side, then transfer it to your slow cooker.
3. In the same skillet, sauté sliced onion and minced garlic until fragrant and tender.
4. Layer the cooked onions and garlic over the roast in the slow cooker.
5. Pour 4 cups of beef broth, 1/2 cup of red wine, and 2 tablespoons Worcestershire sauce around the roast. Scrape up the browned bits from the skillet and add them to the slow cooker for extra flavor.
6. Place the sliced carrots and cubed potatoes on top of the onions in the slow cooker. Add any optional vegetables like baby portobello mushrooms if desired.
7. Cover the slow cooker with its lid, then cook on low for 8-10 hours or on high for 5-6 hours, allowing the meat to become tender.
8. Once cooked, carefully remove the roast and vegetables from the slow cooker.
9. To make the gravy, transfer the cooking liquid from the slow cooker to a saucepan set over medium heat. Whisk together equal parts cornstarch and cold water, then mix it into the liquid until it thickens.
10. Serve the pot roast with the vegetables and the homemade gravy, and enjoy a hearty, comforting meal.