Heat olive oil in a large Dutch oven or heavy skillet over medium-high heat until shimmering. Season beef sirloin tips generously with salt and pepper, then brown for 6–8 minutes total, turning occasionally until golden on multiple sides. Transfer to a clean plate and set aside.

In the same pot, sauté diced onion for 3–4 minutes until softened and translucent. Add minced garlic and sliced mushrooms, cooking another 3 minutes while stirring frequently to deepen flavors. The beef tips over noodles crowd dinner truly begins when these aromatics release their fragrance.

Stir in tomato paste and cook for 1 minute, coating vegetables evenly and allowing paste to caramelize slightly. Pour in beef broth, Worcestershire sauce, dried thyme, and rosemary, scraping any browned bits from the pot bottom. These fond particles contain essential flavor compounds.

Return beef tips to the pot, ensuring they're submerged in liquid as much as possible. Reduce heat to low and simmer gently for 15 minutes, allowing this crowd beef tips noodles mixture to develop deep, complex flavors. The meat should become increasingly tender with each passing minute.

While beef simmers, bring a large pot of salted water to a rolling boil. Add egg noodles and cook according to package directions, usually 8–10 minutes, stirring occasionally to prevent sticking. Drain noodles but do not rinse them—the starch helps sauce cling beautifully.

Taste the beef and sauce, adjusting seasoning with additional salt and pepper as needed. Stir in butter and fresh parsley, then gently fold in drained noodles until everything combines evenly. Serve immediately while flavors remain vibrant.