No, your brain is definitely not weird--you are highly observant.
I would never have noticed that white/black works but black/white doesn't.
I'm wondering if the reason why the White/Black Cake and Salt/Pepper Shrimp Cocktail both work is because they both come from the Up All Night DLC, like the Black and White Party itself.
In contrast, the Black/White Cake is base game, according to Carl's guide on cooking.
Along these lines, Black/White Cookies also come the Up All Night DLC.
Not sure, just speculating here. And, by the way, are you going to join the tournament challenge for kleptos?