Pasta with Tuna and Arugula

1/3 pound pasta (any kind- all I had were tortelli)
1/2 can tuna packed in olive oil
about 1 C arugula
1/4 small onion, diced
1 clove garlic, minced
1 tsp red chili flakes
salt and pepper
juice of 1/2 lemon

This is an easy dish that can be varied in a million ways. You could add capers (I meant to but forgot), or tomato paste, or broccolini, or use anchovies instead of tuna... All I do is quickly sautee the onions and garlic with the chili flakes, add the tuna just to heat it, and then throw the arugula on top and let it wilt while the pasta boils. Then you can just squeeze a little fresh lemon juice into the mixture, toss it with the pasta, and eat! Yum. These quantities serve one, by the way.