I used Emmi Le Gruyere - one of Emmi’s premium specialty cheeses, Le Gruyère® is among the world's most savored cheeses, made from recipes dating back to 1155 AD. To earn the Le Gruyère® AOC label, strict guidelines are followed. The farmer insures that the cows are fed on a naturally sustainable diet pastured grass in the summer and hay in the winter. The cheese is made only in copper vats, which allow quick temperature changes and impart a unique, complex character. As the cheese slowly matures in special cellars, every wheel is delicately turned, lightly brined and brushed. This careful process brings out Le Gruyères® distinctive flavor, with notes of candied walnuts, dried fruit and spice, it melts beautifully and is a luxurious vehicle for the herbs and tomatoes of this tart.