Stir tuna, capers and lemon zest into the sauce. Add drained spaghetti and a generous drizzle of olive oil, and toss well to combine. Add more salt, pepper and/or red pepper flakes as needed.

Once the fresh tuna pasta is ready, it is recommended to consume it immediately. You can prepare the sauce in advance, but ...

Stir in the tuna and salt. Toss the pasta with the sauce, loosening with a little pasta water if necessary. Serve the tuna pasta sprinkled with the remaining parsley and freshly ground pepper.