You should eat at the airport, and bring along something for her to eat during the flight.
an allergen-free meal*.
* This meal is free of the following products and their derivatives: cereals, shellfish, eggs, fish, peanuts, soy, milk, nuts (almonds, walnuts, hazelnuts), celery, mustard, sesame seeds, lupine, mollusks, and sulfur dioxide and sulfites in a concentration exceeding 10 mg/kg.
Information on peanuts
We are sensitive to food allergy issues. As a result, we now offer a special “allergen-free” meal* on certain flights. If you would like this meal, please request it when booking your flight.
* With the exception of the allergen-free meal, we cannot guarantee the absence of traces of peanuts or other nuts in our meals, both on board and at the airport.
My bet on this would be some sort of chicken and rice thing. YMMV