Gather your ingredients and tools.
Slice the onion and soak in a bowl of cold water. Set aside.
Cut the crust from the bread, cut into cubes, and place in a small bowl.
Make a tomato puree by passing one tomato through the food mill over the bread. Season with salt and set aside.
In the bowl of your food processor or using a mortar and pestle, blend the garlic, anchovies and capers into a fine paste. Add the salt, olive oil, and vinegar and combine well. Scrape the mixture into the serving bowl.
Add the chopped sweet bell pepper to the serving bowl. Drain the water from the onion and add to the bowl. Add the chopped cucumbers and stir well.
Seed the remaining tomatoes and chop. Add to the bowl.
Add the bread and the sliced basil*.
Stir the salad well and season with fresh pepper and more sea salt if needed.