Cook the pasta in a pan of boiling salted water according to the packet instructions.
Meanwhile, place a large non-stick frying pan on a medium-high heat with 1 tablespoon of olive oil. Add the capers, fry until super-crispy, then scoop out and put aside, leaving the fragrant oil behind.
Halve and add the tomatoes, then sprinkle in most of the oregano.
Drain and flake in the tuna, add 2 ladlefuls of pasta cooking water, and simmer until the pasta is done.
Drain the pasta, reserving a mugful of cooking water, then toss the pasta into the tuna pan, loosening with a splash of reserved cooking water, if needed.
Taste, season to perfection with sea salt and black pepper, then dish up. Sprinkle over the crispy capers and the remaining oregano from a height, drizzle with 1 teaspoon of extra virgin olive oil, and tuck in.