Stir up tuna salad in a small bowl and set aside.

Cut around the circumference of the tomato using a zig-zag pattern and pull halves apart.

Scoop out the extra tomato from the inside, leaving two shells.

Set up two chilled salad plates and spread the lettuce out to create a bed.

Fill tomato shells with tuna salad and arrange on the plates along with the other remaining plate ingredients.

Serve chilled.