Prepare pesto: Combine all the pesto ingredients with some salt and pepper into a food processor and blend until smooth. Adjust the amount of oil to achieve desired consistency.
Slice your bread in half lengthwise. Spread a generous layer of pesto onto the bread. Place slices of tomatoes and cheese onto bread, alternating the cheese and tomatoes to achieve your desired pattern.
Place the open sandwich onto a lined baking sheet and broil at 180C for 20 minutes or until nicely toasted and golden brown. Garnish with basil, slice and enjoy!