Here's a dish for iconoclasts: tagliatelle with tunafish simmered in butter, cream and parmesan cheese—a dish that violates one of the cardinal rules of Italian cooking: never mix fish and aged cheese. But this may be one of those exceptions that prove the rule, as the result is really very good.
Sauté a can of good quality tuna packed in olive oil, together with a minced anchovy fillet, in some sweet butter, mixing well and shredding the tuna with a wooden spoon as you stir. Add cream to cover and allow the cream to reduce until it reaches the nice 'saucy' consistency. Add a generous amount of chopped parsley and keep warm.
Meanwhile, cook your tagliatelle al dente and add to the pot, along with some of the pasta water and a generous dusting of grated parmesan cheese. Allow the tagliatelle to simmer in the tuna sauce, mixing well, for a minute or two until nicely coated. Serve immediately, with more grated cheese on top if you like.
NOTES: In Italian cooking, pasta dishes with tuna almost always come either in rosso (with a tomato sauce) as in this post, or in bianco, where the tuna is simmered in olive oil, often with a soffritto of garlic and parsley. In either version, capers and olives are often paired with the tuna. But this version is a real departure from these more common versions but you may like it a lot. For readers in North America, on the other hand, the taste will be familiar, reminiscent of a good old tuna casserole.
The same sauce works equally well—perhaps even better—with canned or chopped smoked salmon. I've seen a menu item calling for the addition of saffron, which I have not tried but sounds intriguing. You can omit the anchovy for a milder flavor and/or sauté a bit of finely chopped shallot, white onion or garlic in the butter before adding the fish for a more savory effect.
Besides tagliatelle, this dish would work well with the wider pappardelle or even stubby dried pasta like penne or rigatoni. I would avoid long dry pastas like spaghetti or linguine.
