Two problems: one, it's tiramisu, not tiramasu, but I'd let that slide as a fudge to make the joke work if it weren't for problem two.
Problem two is that the unconjugated form of tiramasu would be tiraru. Except tiraru would be a "godan verb" because the "a" vowel prior to the "ru" ending, which means it would conjugate as tirarimasu and tirarimasen. At this point we've strayed too far from "tiramisu" for the joke to work IMO. Which left me staring at the meme for way too long trying to figure out if it was an attempt at a Japanese joke or not.