Guess Who's Coming to Dinner?

Put a free meal out in your yard, and you never know just who will show up to dinner. (No, not Sidney Poitier.) I was sitting in the living room yesterday and saw a large bird land on the hummingbird feeder in the front yard. 

 Grabbing my iPhone, I began snapping pictures.

Hopeful that the bird would not see me through the window as I approached, I carefully stepped closer for a better view.

 Perfect! I can see the shape of the beak now.

What kind of bird was it that was helping itself to the hummingbirds' nectar?

A female rose-breasted grosbeak.