Pesce Spada alla Stemperata (Sicilian-Style Swordfish)

Alla stemperata is a full-flavored Sicilian way to prepare swordfish or tuna (and sometimes rabbit or hare). For guidance on ecologically friendly fish choices, see Seafood Watch. Giuseppe Coria, in his essential tome Profumi di Sicilia, published in 1981, attributes the dish to Ragusa and Siracusa and says the obligatory ingredients are green olives, c…