you can take whatever customs will permit you to onto the plane, the usual 100ml of liquid unless you have bought it airside etc
if you are planning to take food etc into lapland in your hold luggage then most things can go through except I did see lots of signs about honey on one visit
we have taken loads of food with us when we have gone but you can get everything you need there
heres another tread about this very question
http://www.tripadvisor.co.uk/ShowTopic-g1-i10702-k5487164-Can_you_take_food_on_a_plane-Air_Travel.html
also, if its your first flight them take her something to sip or suck on when the plane takes off and lands so to help with the pressure, also take her a pillow and a blanket and try and get her to go to sleep especially if you are going on a day trip as she will be knackered if she doesnt sleep