Wow, I thought that angelx03 would've guessed it, but *~Kawaii_Animegirl~* got it right. The shot is from the CCS episode about the Illusion card. (While everybody is freaking out about ghosts, Tomoyo-chan imagines a meat bun. )
That from Cardcaptor Sakura?! *bangs head onto desk*
Well, truth of the matter is that I never really owned any of the uncut subbed versions of CCS (except of the bilingual version of the second movie). But nonetheless, I FAILED MY FANDOM!