Don't have a clue what to fix for dinner tonight? This dish is always a great solution to that problem. The tomatoes and parsley are the only fresh ingredients you need; everything else is probably in your fridge or pantry. For a splurge, use Spanish tuna in olive oil; for a bargain, try Genova brand, also in olive oil but half the price.
Bring a large pot of generously salted water to a boil over high heat. Add the pasta, stir, and cook until just shy of al dente (about 1 minute less than the package instructions). Just before the pasta is ready, scoop out about ½ cup/120 ml of the cooking water and set aside. Drain the pasta.
Return the pasta to the pot over medium heat. Add the tomato sauce and toss to coat evenly. Fold in the tuna, olives, and capers, and then fold in a few spoonfuls of reserved pasta water to create a nice saucy consistency.
Divide the pasta among warmed pasta bowls and sprinkle with the parsley. Serve right away.
Modern Sauces, 150 Recipes for Every Cook, Every Day by Martha Holmberg. Chronicle Books 2012.