Summary of "Pasta With Sardines - Mark Bittman | The New York Times"

Ingredients

1 can canned sardines packed in olive oil (buy sardines in olive oil; inexpensive brands are fine)
Fresh breadcrumbs (to toast)
Olive oil (for toasting breadcrumbs and cooking onions/sardines)
1 onion — white or yellow (slice or chop; soften, do not brown)
Lemon zest
Capers
Pasta (he uses “Perkotelli”; any short or long pasta will work)
Salt (for the pasta cooking water)
Parsley (finely chopped, to finish)
Red chili flakes (optional)
Reserved pasta cooking water (used to loosen the sauce)

Large pot of salted boiling water for the pasta
Skillet or sauté pan for the onions, sardines, and to assemble the dish
Small skillet (or the same pan) to toast fresh breadcrumbs in olive oil
Microplane or zester for lemon zest
Tongs or a pasta fork for tossing
Prep: zest the lemon; have capers and parsley ready; start boiling salted water before you begin.

Toast breadcrumbs: heat olive oil in a skillet and toast the fresh breadcrumbs until crisp and golden. Set aside and plan to use them immediately when serving.
Start onions: in a sauté pan, cook the sliced/chopped onion in olive oil over medium heat until tender and sweet — aim for softened, non-browned onions (about 5 minutes).
Start pasta: cook the pasta in the boiling, salted water while the onions cook (follow the usual timing for your pasta shape).
Warm sardines: add the sardines (in their olive oil) to the pan to warm through — you’re not trying to deeply cook them, just heat them.
Flavor: add lemon zest and capers to the onion/sardine mixture.
Combine: when the pasta is done, transfer it directly to the pan with some of the pasta cooking water (do not drain completely). Toss so the sauce coats the pasta and has a glossy, slightly moist finish. Add reserved pasta water as needed to reach a glistening consistency.
Finish: stir in chopped parsley and, if desired, a pinch of red chili flakes. Plate and immediately sprinkle the toasted breadcrumbs on top so they remain crunchy.

Onions: soften for about 5 minutes; avoid browning.
Pasta: cook to package “al dente”; don’t drain completely — keep some cooking water.
Sardines: only need to be warmed in their oil.
Breadcrumbs: toast until crisp; serve immediately for texture contrast.
Finish: toss until glossy; serve hot.

Buy sardines packed in olive oil — it matters for flavor and ease of cooking.
Don’t brown the onions; you want sweet, soft onions.
Don’t drain the pasta completely; a little pasta water is essential to create a shiny, moistened sauce and to help dissolve the sardine oils.
Serve immediately — the dish relies on the contrast between crunchy breadcrumbs and tender pasta/onions; waiting will ruin the texture.
Parsley is recommended; red pepper flakes are optional if you want heat.

Onion: white or yellow both work.
Heat: add red chili flakes for spice (optional).
Sardines: inexpensive canned sardines in olive oil are fine — no need for expensive tins.
Pasta: any pasta shape can be used (the recipe used “Perkotelli”).