doing a project with kosher food?!
Just be careful not to use any milk, butter, or other dairy when you make the onion rings. If you serve the rings with Ranch dressing, make sure there's no dairy in the dressing (most have buttermilk, which would be a no-no at the same meal as brisket)
onion is kosher isnt it? sounds good and some kind of coleslaw might be good.