Preheat oven to 350F.

Drizzle one tablespoon of the olive oil in a large pot {I used my Dutch oven}, and heat to medium-high. Season the roast with salt and pepper, then sear on all sides.

In a food processor, combine the rosemary, garlic, and 1 tablespoon of olive oil, and pulse until finely chopped. Spread the mixture all over the roast.

Roast beef in preheated oven for 45-50 minutes, until internal temperature reaches at least 130F.

While the roast cooks, prepare the mushrooms. In a small pot, combine the butter with the remaining tablespoon of oil, and saute mushrooms until soft and tender. Season with salt and pepper and set aside.

When roast is cooked through, remove the meat from the Dutch oven and bring to stovetop. Deglaze the pot with the beef broth, making sure to scrape up the bits on the bottom. Simmer until thick.

When ready to serve, combine the sauce and mushrooms, and serve with the roast.