Start by seasoning your beef chuck roast with salt and pepper on all sides. Next, chop the onions, garlic, and any additional vegetables you plan to use, such as carrots, celery, and bell peppers.

To enhance the flavor, heat a skillet over medium-high heat and brown the seasoned beef roast on all sides, about 3-4 minutes per side until it develops a nice crust. Once seared, carefully transfer the roast to your slow cooker.

Place the chopped onions and garlic in the slow cooker around the beef, followed by your diced carrots, celery, and bell peppers.

Slowly pour the beef broth over the ingredients in the slow cooker, ensuring the meat and vegetables are well covered.

Cover the slow cooker with its lid and cook on low for 8 hours or on high for 4 to 5 hours.

Once the beef is tender, carefully remove it from the slow cooker and place it on a cutting board. Shred the beef and return it to the slow cooker.

Prepare your mashed potatoes by boiling peeled potatoes in salted water until fork-tender. Drain and mash with butter, cream, and seasoning.

To serve, spoon mashed potatoes onto each plate, top with the shredded beef and drizzle with gravy.