Spread the bread cubes out on a baking sheet and leave out, uncovered, to dry for 24 hours. Alternatively, bake the cubes in a 300 degree F. oven for 10 to 20 minutes until dried out but not toasted.
In a large bowl whisk together the shallots, garlic, lemon rind and balsamic vinegar. Season with salt and pepper. Add the olive oil in a stream, whisking constantly until well combined. Add the tomatoes, bell peppers, fennel and olives, tossing to combine. Adjust seasoning with salt and pepper. Thirty minutes before serving the salad add the reserved fennel greens, basil and bread cubes, tossing to coat, and let the salad stand at room temperature for 30 minutes.
Recipe courtesy of Gourmet Magazine