1 1/2 cups shredded Swiss cheese
1/4 cup butter, softened
1/3 cup packed light brown sugar
1/2 cup milk
1 egg, lightly beaten
1 teaspoon vanilla extract
1/8 teaspoon lemon zest
1 (8 ounce) package cream cheese, softened
4 ounces sliced Swiss cheese
1 tablespoon lemon juice
Preheat oven to 350 degrees F (175 degrees C).
In a small bowl, mix Swiss cheese, butter and brown sugar. Spread mixture over cooled pizza crusts. Rub cream cheese mixture on cheese mixture.
Fold cream cheese mixture into cheese mixture. Fold 2 tablespoons lemon juice over cream cheese mixture. Place sandwich in oven and sprinkle with remaining lemon juice.
Bake in preheated oven for 10 minutes, or until cheese is bubbly.