Step 1: Sear the Beef: Heat olive oil in a large skillet over medium-high heat. Season the chuck roast generously with salt and pepper. Sear the roast on all sides until browned, approximately 3-4 minutes per side. This step enhances the flavor and texture of the meat.
Step 2: Prepare the Vegetables: While the beef is searing, chop the onion, carrots, and celery. Mince the garlic. Quarter the mushrooms.
Step 3: Layer the Crock Pot: Place the chopped onions, carrots, and celery in the bottom of the crock pot. Top with the minced garlic. Place the seared beef roast on top of the vegetables.
Step 4: Add Remaining Ingredients: Add the quartered mushrooms, dried thyme, dried rosemary, and bay leaf to the crock pot. Pour the beef broth over the roast and vegetables. Season with salt and pepper to taste.
Step 5: Slow Cook: Cover the crock pot and cook on low for 8 hours or on high for 4 hours, or until the beef is very tender and easily shreds with a fork.
Step 6: Shred and Serve: Remove the bay leaf. Shred the beef with two forks. Serve the shredded beef and vegetables with the cooking liquid as a flavorful gravy.
Optional: For a thicker gravy, remove about 1 cup of the cooking liquid from the crock pot after cooking. Whisk in 1 tablespoon of arrowroot powder or xanthan gum. Pour the mixture back into the crock pot, stir well, and let it sit for 10-15 minutes to thicken.