Tuna Niçoise Sandwich

This sandwich, our take on the French Pan Bagnat, is perfect for outdoor eating. Its flavour improves when you make it ahead of time.

3 Tbsp. extra-virgin olive oil
2 Tbsp. white-wine vinegar
1 Tbsp. Dijon mustard
sea salt
black pepper, freshly ground
2 (6 oz) cans tuna, oil-packed, drained
¼ English cucumber, thinly sliced
½ small red onion, halved and thinly sliced
1 (8”) round loaf Country-style bread
3 Tbsp. jarred olive tapenade
1 cup fresh basil leaves
2 large eggs, hard-cooked and sliced

In a medium bowl, whisk together oil, vinegar and mustard, season with salt and pepper. Transfer 2 Tbsp. dressing to another bowl; toss with tuna. To remaining dressing, add cucumber and onion; toss to combine.

Cut bread in half horizontally; remove most of soft interior crumb. Spread tapenade on bottom half. Top with basil leaves, then egg slices; season with salt and pepper. Top with tuna, then cucumber mixture; close sandwich.

Wrap sandwich tightly in plastic and place between two baking sheets. Weight with a heavy skillet. Let stand 1 hour (or refrigerate, up to overnight). To serve, cut into quarters.

Makes 4 servings.