1. Finely chop the onion and wilt it in a pan with a little olive oil. Break the white tuna into small pieces.
  2. When the onion is golden brown, add the cherry tomatoes cut in half.
  3. After a couple of minutes, add the tuna and let it roast; once browned, deglaze with white wine.
  4. Once the alcohol has evaporated, add the tomato sauce, adjust the salt and let it cook on a low flame for about 30 minutes.
  5. Clean the broad beans, blanch them quickly in water and immediately plunge them into ice water.
  6. Cook the Gramigna in plenty of salted water, drain the pasta al dente and transfer it to the pan with the tuna sauce.
  7. Stir-fry it with a little cooking water and the broad beans, until perfectly blended. 
  8. To finish, plate the Gramigna by grating some Pecorino Romano cheese.