Gazpacho Sandwich

Name: Gazpacho Sandwich
Ingredients: 1/2 cup crumbled feta cheese; 3 tablespoons good quality extra-virgin olive oil; 2 tablespoons sherry vinegar; 2 teaspoons Dijon mustard; 1/8 teaspoon freshly ground black pepper; 1/8 teaspoon kosher salt; 1 shallot, chopped; 1 round loaf sourdough bread, cut into 1/3-inch-thick slices; 3 to 4 ripe tomatoes, thinly sliced; 1/4 teaspoon kosher salt; 1 medium cucumber or 1/2 English cucumber, peeled and sliced into thin rounds; 1 yellow pepper, sliced into thin strips; 2 cups arugula; 1/4 cup roughly chopped fresh basil; 1/4 cup roughly chopped fresh cilantro; 1/4 teaspoon freshly ground black pepper