Peperoni Ripieni con Tonno (Bell Peppers Stuffed with Tuna)

The forerunner of this antipasto from Piedmont in Italy was probably peppers with anchovy sauce; both are still made and are excellent. The tuna in question is canned, and it’s important to avoid bluefin and any other threatened species (see Seafood Watch) and to use a better-quality brand than the usual North American ones, which taste slightly fishy a…