Preheat oven to 250 degrees.

Rub Garlic-Rosemary rub in the chuck. Cover loosely with plastic wrap, and let rest at room temperature for 30 - 60 minutes.

Roast the meat in a shallow pan for 30 minutes then lower to 170.

Continue to roast for 4 to 6 hours, or until internal meat thermometer registers 120 degrees to 125 degrees.

Allow the meat to rest, tented loosely with foil for 5 to 10 minutes before slicing and serving.