Gather your ingredients. Set your griddle / stove for low heat. The key to getting a golden crust and melted cheese is low (or medium depending on your stove) heat.
Place the first layer of cheese on the bread.
Spread the pesto on top of the cheese. You really don't need too much.
Add your filler!
Top with the second layer of cheese.
Apply the olive oil (or butter) lightly to one side and then place down on your griddle or pan. Then apply a light layer to the top piece of bread.
I covered my sandwich to ensure the cheese would melt before the bread burned. Flip the sandwich when the first side is golden brown and brown the other side.
Serve & Enjoy!