Grilled cheese sandwich with pesto, tomatoes, Gouda and Parmesan cheeses.
Butter one side of each slice of bread.
Place 4 buttered slices on a cutting board or baking sheet with the buttered side down.
Spread pesto onto each of the 4 slices. Add tomatoes, Parmesan and Gouda cheeses. Place remaining bread on top with buttered side up.
Preheat a griddle or a cast iron skillet on medium heat. Place 1-2 sandwiches on griddle. Cook for 2-3 minutes until bottom bread is nicely browned. Flip sandwiches and continue cooking for 2-3 more minutes until other side is brown and cheese is melted throughout. Repeat with remaining sandwiches.