The catering at the Finnair non-schengen lounge depends a lot on the time of the day. Last Sunday in the afternoon they didn't have anything warm on offer. Just some salads and nice bread. But last time I flew on the midnight departure to SIN I was able to have an okay warm dinner before the flight.

The food outlets air-side are a bit overpriced to me but at least the recently opened O'Learys sports bar next to gate 29 has good burgers. Land-side when looking for a cheap place Cesar's Pizza & Food Court in the service floor (below arrivals level) is a good alternative.