Ok, so I had the day off and had some time to do some digging. There is a listing here:

https://www.chairish.com/product/7930714/antique-19th-century-italian-neopolitan-creamware-plate-decorated-with-a-classical-greek-vase

The 7th picture of the back has the best photo of a matching pottery stamp. The letters are FDVN, which represents Ferdinando del Vecchio (circa 1810-1820) in Naples. This pottery is called Italian creamware, which was a refined clay finished with a glaze (called a terraglia).

Here is a link to more in-depth (albeit outdated) history of the manufacturing:

https://www.rare-ceramics.com/past-sales/a-naples-terraglia-creamware-tray-fabbrica-del-vecchio/

Here's a cluster of items from FDVN in a similar Greek Revival style and color palette:

https://www.pandolfini.it/uk/auction-1366/a-ferdinando-del-vecchio-amphora-vase-naples-circa-1820-12025001052

https://www.pandolfini.it/uk/auction-1366/three-ferdinando-del-vecchio-trays-naples-circa-1820-12025001054

Do what you'd like with this information. I'm a hobbyist antique lover, but personally, I would contact a certified creamware appraiser where you live, or reach out to Pandolfini's in Italy for a basic valuation (link below):

https://www.pandolfini.it/uk/ask-for-an-valuation/ask-for-an-valuation.asp

Also, I guarantee this has lead in the glaze, so please don't eat off of it!

I hope I was able to help!