- 1/2 pound spaghettini
- 2 tablespoons red wine vinegar
- 1/2 teaspoon grated orange zest
- 1 tablespoon fresh orange juice
- 1 tablespoon lemon juice
- 1 teaspoon Dijon mustard
- Salt
- Fresh-ground black pepper
- 6 1/2 tablespoons olive oil
- 2 cucumbers, peeled, halved lengthwise, seeded, and cut crosswise into thin slices
- 6 tablespoons chopped fresh mint
- 1 pound tuna steak, about 1 inch thick
- In a large pot of boiling, salted water, cook the spaghettini until just done, about 9 minutes. Drain. Rinse with cold water; drain thoroughly.
- In a large glass or stainless-steel bowl, whisk together the vinegar, orange zest, orange juice, lemon juice, mustard, 3/4 teaspoon salt, and 1/4 teaspoon pepper. Add 6 tablespoons of the oil slowly, whisking. Add the spaghettini, cucumbers, and mint and toss.
- Heat a grill pan or heavy frying pan over moderately high heat. Coat the tuna with the remaining 1/2 tablespoon oil and sprinkle with 1/8 teaspoon salt and a pinch of pepper. Cook, turning once, until done to your taste, about 2 minutes per side for medium rare. Remove. Cut the tuna into 1-inch chunks and toss with the spaghettini.