Pat beef chuck dry with paper towels and season generously with salt and pepper. Heat 2 tablespoons olive oil in a large Dutch oven or heavy-bottomed pot over medium-high heat until shimmering and nearly smoking—about 2 minutes. Sear beef in batches for 3-4 minutes per side, avoiding crowding the pan. Transfer to a plate once browned; do not skip this step.

Reduce heat to medium and add diced onion to the pot with rendered beef fat. Cook for 4-5 minutes, stirring occasionally until onions soften and turn translucent. Add minced garlic and cook 1 minute until fragrant—this builds aromatic foundation that CIA chefs recognize as the flavor base.

Stir in tomato paste and cook 2 minutes, allowing it to caramelize slightly against the pot bottom. This concentrates the paste's umami and eliminates any metallic taste. Add all seared beef back to the pot along with beef broth, beef stock, bay leaves, and dried thyme.

Bring to a gentle simmer, then reduce heat to low and cover partially. Simmer for 15 minutes until beef begins tenderizing, stirring occasionally. Add carrots, celery, and sliced mushrooms, then simmer uncovered for another 10 minutes until vegetables are tender-crisp and the best beef and noodle soup recipe shows its structure.

While vegetables finish, bring a separate pot of salted water to a boil and cook egg noodles according to package directions—typically 7-8 minutes. Drain well but do not rinse; starch helps them absorb broth. Add cooked noodles to the soup in the final 2 minutes and adjust salt and pepper to taste.