Season and sear the roast

• Season the roast generously on all sides with salt, pepper, onion powder and garlic powder.
• Sear in a hot skillet with a little oil for 3–4 minutes per side until nicely browned.
• Remove and set aside.

Sauté the vegetables

• In the same pan, sauté the onion and celery for a few minutes until softened and the onion starts to caramelize.
• Add the garlic and cook for about 30 seconds.

Build the gravy

• Stir in the tomato paste and Worcestershire sauce and cook for 1–2 minutes.
• Slowly add the beef broth, scraping up all the browned bits from the bottom of the pan.
• Whisk in the Au jus packets and spices until smooth.

Load the crockpot

• Transfer the gravy mixture to the crockpot.
• Place the potatoes and carrots in the bottom of the crockpot, then place the seared chuck roast on top.
• Add the butter and a generous amount of rosemary and thyme tied together with butcher's twine.

Cook low and slow

• Cover and cook on LOW for 8–9 hours (preferred for a tender roast) or on HIGH for 4½–5½ hours.

Finish and serve

• Remove the rosemary and thyme bundle.
• Taste the gravy and adjust salt and pepper if needed.
• Serve over creamy mashed potatoes, spoon the pot roast, carrots, potatoes and plenty of gravy over the top.
• Finish with fresh parsley.