01 -  Spread one side of each slice of bread with softened butter. 
 02 -  Flip the bread slices and spread 1 tablespoon of pizza sauce on the unbuttered side of each slice. 
 03 -  Arrange mozzarella slices, tomato slices, and fresh basil leaves on two of the bread slices, sauce side up. 
 04 -  Sprinkle grated Parmesan, salt, freshly ground black pepper, and dried oregano if desired evenly over the cheese and vegetables. 
 05 -  Top with the remaining bread slices, keeping the sauce side facing in and the buttered side facing out. 
 06 -  Heat a nonstick skillet over medium-low. Place the sandwiches in the skillet and cook for 3 to 4 minutes per side, pressing gently, until the bread is golden brown and the cheese has melted. 
 07 -  Remove sandwiches from the pan, allow to cool for 1 minute, then slice and serve immediately.