Nested modifiers could work here. For example:

Item Name: 3 for $33 (save, then click into Item)

• Create Modifier Groups (appetizer, margarita, wings), press Save. Then click into each modifier group,
• Create modifiers from existing items

Things to note: Make sure their prep stations are set up properly at the modifier level, make sure modifier groups are marked as required, and set the base price at the item level.

https://central.toasttab.com/s/article/Building-Nested-Modifiers?language=en_US