- 1 (4 pound) piece of swordfish, about 2-inches thick
- ¼ pound unsalted butter, melted
- ½ cup fine sea salt
- ¼ cup dry gin
- 3 tablespoon fresh lime juice
- ¼ pound plus 4 tablespoons (1¼ stick) cold unsalted butter, cut into bits, chilled
Prepare the fish: Pat the swordfish dry with paper toweling rand place on a large platter or pan.
Brush the top side with half of the melted butter. Dredge liberally with half of the salt.
Refrigerate for 20 minutes until the butter has congealed. Carefully turn the fish, brush the other side with the remaining melted butter and dredge with the remaining salt. Refrigerate for another 20 minutes, or until ready to grill. Build a-charcoal fire in an outdoor grill.
Prepare the gin-lime butter: In a small nonreactive saucepan carefully bring the gin and lime juice to a simmer over medium heat. Be sure not to splash any of the liquid into the burner or the gin could ignite. Cook until reduced to a thick glaze, about 7 minutes.
Remove from the heat and whisk in 2 tablespoons of the butter, piece by piece. Return to low heat and, whisking constantly, add the remaining butter piece by piece. The sauce should have the texture and consistency of a thick creamy hollandaise. Remove from the heat. Set aside and keep warm until ready to serve with the fish.
When the coals are dusty and glowing, spread them out in the grill, banking them slightly against the sides. Place a sheet of heavy foil in the center. (This will prevent the melting butter from dripping onto the coals, flaring up, and burning the fish.)
Grill the fish for 10 minutes. Turn and cook for 7 more minutes. If the butter should flame up, cover the grill for a minute or two until the flames die down. The fish should be moist and tender. Cut the fish crosswise into thick slices and serve with the gin-lime butter.