Tuna Niçoise Salad with Tahini Dressing

Name: Tuna Niçoise Salad with Tahini Dressing
Ingredients: 3/4 pound carrots (about 6), cut into 2-inch pieces, halved or quartered lengthwise if thick; 3 tablespoons extra-virgin olive oil; Kosher salt and freshly ground pepper; 1/2 pound green beans, trimmed, halved if long; 2 large eggs; 1/4 cup tahini; 2 tablespoons white wine vinegar; 1 small head red-leaf lettuce, torn; 2 5-ounce cans tuna in olive oil, drained; 8 radishes, thinly sliced; 16 pitted kalamata olives; Za'atar spice blend, for sprinkling