My Dog Drank My Choc Milk!

I made a big mug of chocolate milk to go with my home made spicy tacos after a late night working and ran down to the basement to chuck a load of laundry in. What does that take, 30 seconds? I come back upstairs and Maxi's licking her chops and has white stuff all over her muzzle. I look at my glass on the coffee table and all that's left is doggie backwash. Blech! :D I don't think I'll ever use that mug again.

I'm suprised it didn't make her sick. I know how bad chocolate is for a dog so I kept an eye on her, but she's fine.