Heat olive oil in skillet, toss bread in oil and toast until golden. Set aside to cool.
Cut the tomatoes, keeping them about the same size as the bread (hint: slice horizontally into the thickness you want, lay the slice down flat, and cut into cubes). Set the cubed tomatoes on a sheet pan lined with paper towels and salted them lightly to drain and changed the paper towels a few times.
To make dressing, combine olive oil, Champagne vinegar, salt, pepper, Dijon mustard, and Worcestershire sauce
Toss all the vegetables in the bowl with the bread, and toss with enough dressing to moisten the bread. Top with Grana Padano and season with salt and pepper.