There's a meme on reddit where the users tend to ask,
When does the narwhal bacon?
The only correct answer to that question is
What is the etymology and the meaning of this question?
I believe that its origin was here, formed as a passphrase to identify fellow reddit users. Bacon and narwhals were popular topics of discussion on reddit at the time.
Bacon and narwhal are both popular words on reddit and in other internet communities, because bacon is delicious and horned sea creatures are awesome. They serve as in-jokes or memes, and don't have much real significance beyond that.
Grammatically speaking, the word bacon is indeed being used as a verb. This is part of what makes the phrase nonsensical, because bacon has no established meaning as a verb.
If you really want to find meaning in the phrase, you could imagine that the narwhal is doing something with bacon, such as producing or distributing it. On the other hand, finding meaning in nonsense is probably missing the point.