1. In small bowl combine Parmesan cheese, basil and garlic. Sprinkle over one side of each tomato slice. Set aside.
2. Brush cut sides of focaccia with olive oil. Set aside.
3. Coat cold grill rack with nonstick coating. Preheat grill. Place patties on grill rack over medium heat. Grill for 6 minutes. Turn patties. Grill for 2 minutes more. Top each patty with cheese slice, if desired. Place tomato slices, Parmesan side up, and bread pieces, oil side down, alongside patties on grill rack. Grill about 2 minutes more or until cheese begins to melt and bread begins to brown.**
4. Arrange spinach on half of the bread pieces. Top with patties, tomato slices and remaining bread pieces. Serve immediately.
*Note: If desired, substitute one ciabatta loaf for the focaccia
**Note: If desired, prepare in oven. Bake patties according to package directions. Top each patty with cheese during the last minute of baking, if desired. Remove from oven. Keep warm. Place tomato slices, Parmesan side up, and bread pieces, oil side up, on shallow baking pan. Broil 4-inches from heat for 3 to 4 minutes or until cheese begins to melt and bread begins to brown. Assemble sandwiches as directed above. Serve immediately.