For the vinaigrette; combine all the ingredients in a large bowl. Juice half the lemon and add to the dressing, season. Whisk until well combined.
Add the tomatoes to the dressing, toss to coat. Cover and refrigerate 1-2 hours if time permits, gently stirring every 30 minutes.
Preheat oven 200°C fan forced. Spray both sides of bread slices with oil and arrange in a single over two large trays. Bake 10 minutes or until golden and crisp. Set aside to cool. Transfer to a large platter or board. Combine the parsley and basil and scatter over the cooled bread.
Pit the olives and add to the tomatoes. Stir to combine then spoon over the herbs and bread. Serve immediately.