Tuna Nicoise Sandwiches

Name: Tuna Nicoise Sandwiches
Ingredients: 3 large eggs; 1/4 cup mayonnaise, plus more for serving; 2 tablespoons white wine vinegar; 2 teaspoons Dijon mustard, plus more for serving; Kosher salt and freshly ground pepper; 2 jars (7 to 8 ounces each) good-quality tuna packed in olive oil, drained; 1 large baguette, cut crosswise into 4 pieces and split open; 1/4 cup kalamata olive tapenade; 2 plum tomatoes, thinly sliced; 1/4 English cucumber, thinly sliced; 2 radishes, thinly sliced; 8 leaves butter lettuce; Potato chips and pickled green beans, for serving