This is one of my all-time favorite recipes, and it works with any meaty fish, including bigeye or yellowfin tuna and domestic Atlantic mahimahi. These big fish contain some mercury, but enjoying them occasionally is fine. Serve this dish on its own for a light meal, or pair it with roasted potatoes to satisfy heartier appetites.
Olive-Crusted Tuna with Spinach Ragù
For the tapenade
- 1/2 cup (3 oz.) pitted kalamata olives
- 1 Tbs. chopped fresh flat-leaf parsley
- 1 anchovy fillet, rinsed and dried
- 1-1/2 tsp. capers, rinsed and drained
- 1 small clove garlic, finely chopped
- 1/2 tsp. finely grated lemon zest
- 2 Tbs. extra-virgin olive oil
For the fish and ragù
- 2 oz. (4 Tbs.) unsalted butter
- 12 cherry tomatoes, quartered
- 1/4 cup raisins
- 2 Tbs. fresh lemon juice
- 2 Tbs. toasted pine nuts
- 5 oz. (5 packed cups) baby spinach
- 1 Tbs. finely grated Parmigiano-Reggiano
- Kosher salt and freshly ground black pepper
- 4 1-inch-thick tuna steaks (about 5 oz. each)
- 1 Tbs. extra-virgin olive oil
Make the tapenade
- Process the olives, parsley, anchovy, capers, garlic, and lemon zest in a food processor until finely chopped. With the motor running, gradually add the oil and process until combined. Reserve 1/4 cup for the fish; refrigerate the remainder in an airtight container for another use.
Cook the ragù and the fish
- Melt the butter in a 12-inch nonstick skillet over medium heat. Cook, swirling occasionally, until fragrant and the milk solids are golden brown, about 2 minutes. Stir in the tomatoes, raisins, lemon juice, and pine nuts. Add the spinach and stir until just wilted, about 2 minutes, then stir in the Parmigiano, 1/2 tsp. salt, and 1/4 tsp. pepper. Transfer to a bowl and cover with foil to keep warm. Wipe out the skillet.
- Pat the tuna dry and lightly season with salt and pepper. Heat the olive oil in the skillet over medium-high heat until shimmering hot. Add the tuna and cook, undisturbed, until the bottom 1/8 inch is whitened for medium rare (1/4 inch for medium), about 1 minute. Flip, spread the reserved tapenade over the top, and cook until the bottom 1/8 to 1/4 inch is whitened but the center is still red, about 1 minute more. Serve with the ragù.