The full Aer Lingus short haul menu is pictured below. Vegans can have olives for €3.50. Vegetarians do somewhat better: ciabatta melt €5, scone with butter and jam €3, brie and grape sandwich or egg and rocket €5.
Note: Aer Lingus has recently introduced a pre-order possibility for chicken noodle salad, beef noodle salad and full Irish breakfast, each €7.50. There are no pre-order options for vegetarians/vegans.