Can you outfish, out-fish, or out fish someone?

I don't even know what to Google in order to find the answer to this question.

I'm trying to determine the proper grammar for outdoing someone in a particular area. For instance, in the previous sentence, I comfortably used the word "outdo" as a single word with no hyphen, and the dictionary supports this. However, what about fishing better than someone? Wiktionary believes that "outfish" is a word, but Microsoft Word and other dictionaries disagree. Since in English, unlike in German and other languages, we don't typically mash words together to get a single valid word (at least not without a hyphen), my question is as follows.

Which of the following is the correct way to express fishing better than someone: outfish, out-fish, or out fish?

I would say out-fish. There is no such word as outfish to my knowledge, and to "out fish" would be to expose hidden fishness.

Out- is a productive prefix, which in my book means you can create new "words" by putting it in front of a wide variety of verbs and nouns. Here, for example, is a piece in the Los Angeles Times writing of Republican presidential nomination candidates trying to out-Reagan Reagan.

I don't think the hyphen is particularly required in more mundane constructions like outfish - I'd only use it in more "exotic" coinages like the one above, or where the lack of a hyphen detracts from ease of reading. It would never be correct to have a space.

Definitely not out fish. Whether you use outfish or out-fish is really a matter of context and personal preference. Out- is a productive prefix in English - meaning that you can attach it to basically any verb to form a meaningful new verb (to out-X someone is to do better than someone at X)

Some out- compounds have been used often enough that they appear in dictionaries (outdo, outrun, etc.) while others (outfish) haven't - but any native English speaker would immediately understand what outfish means, which makes it a "valid word" by my estimation.

Personally, I would probably write outfish most of the time. If it was very formal writing, however, I might write out-fish, to convey my consciousness of the fact that I'm "making up" this compound and that it isn't found pre-formed in the dictionary.