Everything about this tart screams summer, from the cheery lines of sliced tomato to the ribbons of lemony cucumber. Eat a slice, shut your eyes and you will instantly be transported to the Aegean. Bake the tart ahead of time, because it’s perfect served at room temperature. If I am taking it on a picnic, I like to tub up the cucumber ribbons separately, then squeeze over the lemon and crumble in the feta just before serving.
