This has long been my favourite quick emergency meal. It does no harm at all that every kid I've fed it to loved it.
Total time: 20 minutes
1 lb long thin pasta
1 or 2 cans olive-oil-cured tuna
Bunch of Italian Parsley
Boil and drain the pasta, while washing and cutting the parsley. Empty the tuna can, including oil, into the pasta, break it up into decent pieces, then add the parsley and toss. I like to season to taste with fish sauce, but salt is fine.
You can kick the recipe into the stratosphere by swapping in nice jarred tuna, but the basic version is plenty satisfying.
The illustrated can costs about $2, and the company makes three or four variations using different tuna. I always keep a stack of them on hand.