Preheat oven at 300 degrees.
First, add the potatoes, carrots, and celery to a roasting pan. Season with salt pepper, and 1 packet of onion soup mix.
Next, add the brisket to the middle of the veggies and season both sides of the beef with salt, pepper, and 1 onion soup packet.
Now, add all the onion ontop of the brisket and seaon with a pinch salt and pepper.
Optional: Place the brisket in the fridge overnight. This will give the seasoning time to seaon all through the brsiket not just the surface.
Next, when ready to cook, add beef broth to the roasting pan and cover tightly with tin foil
Now, cook the brisket for 6 hours in the oven at 300 degrees. When done take the beef out and let rest for 15 minutes so the juices stay in the brisket.
Finally, enjoy and happy eating!