"Alan-bashing" could mean "making fun" of Alan.  But it could also mean criticizing him <em>harshly</em> or making accusations against him.   

"Bashing" is a slang term in English meaning to mock or criticize someone or something (not a nice thing to do). The phrase comes from physically bashing something, meaning to hit it. For example, if you and your friends don't like a movie, you might make fun of it - you are "bashing" it. 

So in your example, "Alan-bashing" would be people making fun of criticizing Alan. I'm not sure exactly what that would be based on your example. Where did it come from? 

But simply, "Alan-bashing" is a way of saying "bashing Alan" meaning "making fun of Alan." Hope that helps!

Charlie is right with his explanation :)

I recognize this from an episode of Friends! I am guessing this is where you got it.

The joke in that episode is that Monica's friends tend to really dislike her boyfriends. She assumed  naturally, that Alan would be no exception, so as soon as he left she assumed her friends would start "bashing" him right away!

Thank you all! Appreciate the help.

PS. Yes, this is coming from Friends' episode.

Thank you all! Appreciate the help.

PS. Yes, this is coming from an Friends' episode.