I don't particularly agree with the premise of this chapter of How to Read Literature like a Professor, but in the spirit of literary discourse I'll offer one example of a meal in literature that can be read through a communion lense.
The meal shared in the opening chapter of All the King's Mencan be construed as a communion. This meal emphasizes the shared fate of each character present - Willie, Jack, Sugar-boy, Duffy, Lucy and Tom Stark. If we read this as a communion, we can extend the trope to include a suggestion of Willie's eventual martyrdom.
An example of a meal that is not a communion at all, but, if anything, the opposite, can be found in The Great Gatsby. When Nick visits Daisy and Tom and shares dinner with them (and Jordan Baker), the dynamic is not one of communion. The disfunction of the group (characterized by deception, prurient fascinations, gossip, and general falsness) is displayed. Nothing is shared collectively.
Not every meal is a communion.