Karky: He'll eat almost anything, but while most would assume his favorite is seafood, Karky actually loves pie! He finds them fascinating because they're so antithetical to food you get form the ocean, and he likes apple pie in particular.
Blueberry: I said in a previous answer that he likes hot fudge sundaes with almonds, but aside from that he's very fond of sweets that contain honey. Since skunks love honey!
Francis: He likes a lot of standard "American" food, especially burgers and pan pizza. He may or may not also like bananas or banana-flavored things, but if you ask him about it he'll instantly deny it.
Rokko: He likes sweets in general, but he has a particular weakness for berry-flavored pastries and drinks. He also eats a lot of protein-rich foods, kind of like... well, a bear!
Lashuz: He loves fried catfish. Enough so that you could potentially bribe him with it.
Isaku: He enjoys a lot of normal traditional Japanese dishes, though his favorites might be pork onigiri and yakitori. He also likes honey just like Blueberry, but he keeps it a secret since he thinks it's unmanly.
Dango: Naturally, he likes dango! Also tanuki oden