Tuna Nicoise Sandwich

Ingredients

• 1/2 white onion thinly sliced
• 1/2 red onion thinly sliced
• 1/4 cup plus 4 teaspoons extra-virgin olive oil
• 2 tablespoons red wine vinegar
• Coarse salt and freshly ground pepper
• 2 jars (7 ounces each) best-quality tuna packed in olive oil
• 1 tablespoon fresh lemon juice plus lemon wedges, for serving
• 4 small ciabatta rolls split horizontally
• 2 heads Bibb lettuce leaves split horizontally
• 1 1/2 cups nicoise olives pitted
• 8 hard-boiled eggs peeled and thinly sliced

Instructions

1. 1
   Put onions, 1/4 cup oil, vinegar, and 1/4 teaspoon salt in a medium bowl; season with pepper. Toss to combine. Let stand 10 minutes.
2. 2
   Add tuna and its oil to onion mixture. Add lemon juice and 1/4 teaspoon salt; season with pepper. Gently toss to combine.
3. 3
   Cover bottom halves of rolls with lettuce. Top with olives, eggs, and tuna mixture, dividing evenly. Drizzle each with 1 teaspoon olive oil. Cover with top halves of rolls. Serve with lemon wedges.