It's from the Warner Brothers film Grind. Just watch the movie and you should see what happens next. Based on the music at the end of the clip, it'll go to another scene.
GreetingCard said: I've never seen or even heard of this movie. What's the context behind this scene?
The girl works for a circus, hence all the clown props and implied skills in pie throwing. Sadly, the brief clip above -- and that is the whole scene -- is the extent of what we learn of her prowess with projectile pastries.