Add olive oil to a large cast iron skillet. Over high heat sear the tomatoes until they are caramelized on the outside and become tender, about 2-3 minutes on each side.

Meanwhile, place bread in a single layer on a baking sheet and place under the broiler for 2-3 minutes to crisp up. Keep and eye on them so they do not burn.

Take out of the oven and spoon some pesto onto each crostini. (You will have pesto leftover).

Next place 1 slice of cheese onto each crostini. Place them back under the broiler until the cheese has melted.

Take out of the oven and top with the blistered tomatoes and a drizzle of balsamic reduction.

Garnish with extra fresh chopped basil if desired. Serve immediately.

Add all of the ingredients to a food processor. Pulse until combined. Season with salt and pepper to taste. Set aside until you are ready to assemble your crostini.

Add balsamic vinegar and brown sugar to a small saucepan. Simmer for 10 minutes or until the sauce has reduced by half. Keep warm until ready to use.