Tear bread into bite-sized pieces. Preheat the oven to 350 degrees F. Bake the bread on a baking sheet for 15 minutes, or until lightly toasted.
Combine the next 6 ingredients in a large salad bowl. Add the toasted bread, tomatoes, cucumber, onion, olives and tuna, then toss to combine. Let the salad sit 10 minutes to allow the bread to absorb the flavours. Toss in the lettuce. Divide the salad among 4 to 6 plates. Decorate the top of each salad with boiled egg and serve.