Set the roast out for 20 minutes before you begin. Preheat the oven to 325 degrees. Season all sides of the beef with salt and pepper.
4 Pounds Chuck Roast, Salt and Pepper
In a large pot, heated over medium high heat, add the oil. Once shimmering, add the beef. Brown each side of the roast for a few minutes or until golden. Remove to a plate and add any accumulated juices.
3 Tablespoons Olive Oil
Turn the heat down to medium and add another drizzle of oil. Add the onions and a pinch of salt and pepper and cook for 3-5 minutes.
1 Red Onion, Salt and Pepper
Halfway through cooking, add the mushrooms, stirring occasionally until softened. At this point, add the vinegar and a little water to deglaze the bottom of the pan with a wooden spoon. Turn off the heat.
4 Ounces Baby Bella Mushrooms, 1/4 Cup Red Wine Vinegar, Water
Sprinkle 1/3 of the wild rice and barley, sprinkle with a quarter of the seasonings, including the au jus. Repeat again, and season again. Add the final third of the grains and seasoning, with some remaining to go over the beef.
1 1/2 Cups Wild Rice , 1 Cup Pearl Barley , 1 Packet Au Jus , 1 teaspoon Onion Powder , 1 teaspoon Garlic Powder , 2 teaspoons Oregano
Place the roast on top of all the grains and sprinkle the final of the seasonings over. Add 8 cups of beef broth, balsamic vinegar and Worcestershire and place the lid on the pot and slide into the preheated oven.
Cook for 4-6 hours, checking every 2 hours and adding broth or water as needed so that it's not dry. Remove the pot from the oven and shred the meat. Add it back into the pot and then add the remaining broth, or until desired thickness.
16 Cups Beef Broth , Water
Water can be added as well if you run out of broth. Heat over the stove until the broth is warmed.
Place a little spinach in a bowl and pour the soup over the top with a good shaving of parmesan cheese.