I have problems only oc…er, seldomly

When I'm not quizmastering, I'm a copy editor. As such, I'm a pretty capable speller, and one of the many incredibly sucky things about my school system growing up was that we never had anything remotely like a spelling bee; if you couldn't do a lay-up or crab-walk fast, you were SOL in competitive endeavors.

But, there is one word that is the absolute bane of my existence: "occasional." I literally never remember how to spell out it, and just now typed it in incorrect twice before the red underline disappeared to indicate I'd hit pay dirt.

What's going on here? Is it some mysterious mental block? Like when I was in high school and I somehow always forgot to call my parents at 11pm and tell them where I was? Do I harbor some kind of subconscious resentment of "oca"…"occass"…fuck!…"occasional"?

See, what I really need to do is come up with some kind of mnemonic trick or association to help me easily remember the spelling; that's how I mastered "minuscule" (it includes "minus"—I got a million of 'em). Incredibly dorky suggestions are welcome.