First things first, though. What is this recipe even for? (This dish may not be familiar to you, so I'll allow Google for today's puzzle; it's not entirely trivial to figure out what to search for!)
Then, once you think you know what dish this is, what, in your opinion, does it need 2 Tbsp of?
As for the bonus, perhaps you'd like to give Antonio Vivaldi's Four Seasons a listen?
Solution
Each "quartet" is called The Four Seasons. The art is by Giuseppe Arcimboldo and Alphonse Mucha. Both the ingredients of the pizza and the "ingredients" of Arcimboldo's portraits are seasonal vegetables, fruits and flowers.
Congratulations to yesterday's solvers Lemonade (and Allie)🎻, Charlie🎻, Parley🎻, Atticus, Yana🎻, Mr. Gregg, and Dr. Yetman🎻. Thanks to everybody who made a guess!
Ten years later, Dr. Shapiro revived Puzzle of the Day at Proof School, writing each day's puzzle on a name tag. After 600 puzzles or so, he was just starting to feel normal about students reading his chest all the time when campus closed and the puzzle, like the rest of our lives, moved online. New puzzles are posted daily on school days.
Want to catch up on old PotDs? There's an archive currently containing puzzles from March to June 2020.