dish has been used figuratively for a long time:

1606 Shakes. Tr. & Cr. v. i. 10 Thou full dish of Foole. 1608 I Per. iv. vi. 160 My dish of chastity. 1708 Motteux Rabelais v. vii. (1737) 24 Roger+had a Dish of Chat with her. 1753 Gray Lett. Wks. 1884 II. 241 To entertain you with a dish of very choice erudition. 1820 Lady Granville Lett. (1894) I. 183 This new dish of Continental troubles. 1836 Backwoods Canada 183 For the sake of a dish of gossip.