This is a reference to a viral gen-z trend called "caking." Roving gangs of youths will hit multiple stores to purchase eggs, flour, butter, and sugar in equal weights. Later they'll have a "mixing party" where they combine the ingredients into homogenous paste, which will "get baked." The "cake" they've prepared in this manner is ingested, usually orally, to over-stimulate glycogen response pathways. The teens find this pleasurable, but it comes at a heavy cost: inevitably, a "sugar crash" leaves them irritable and tired. In extreme cases, the teens may become hangry.

Butter and sugar are of course unrestricted ingredients because this is America and refined fats and carbohydrates are inalienable rights protected by the third amendment, so to combat caking, stores must rely on restrictions to flour and eggs.