Heat oil in a wide frying pan, sauté shallots and garlic. Add the tuna and lemon zest, pour in the soup, bring to the boil, reduce the temperature, simmer gently with the lid on for about five minutes.
Mix in crème fraîche, add capers and parsley, just until hot, season.
In the meantime, make pasta al dente, drain.
Mix sauce with hot pasta, garnish.
Note: caper apples are fruits of the caper bush. Capers, on the other hand, are the flower buds that are harvested just before they open.