I've seen 3 versions of the verb used in media:
Which one would be the most correct?
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They're all commonly used and acceptable. The OED lists "tase" and "taser" as verbs, but the American variant "taze" also seems to be widespread.
You may want to refer to this article on the subject.
In the end, for such a recently coined word, it's conventional usage that defines correctness, so you're probably good with any of the above three variants, at this point in time.