Step 1

Preheat oven to 400°F.

Step 2

In a large skillet, heat olive oil and butter over medium-high heat. Stir in onions, salt, pepper and sugar. Cook until onions are caramelized, about 20-25 minutes.

Step 3

Add in beef broth, sherry, Worcestershire sauce and thyme sprigs and cook for 5 minutes or until liquid is evaporated. Remove from heat and set aside.

Step 4

Stretch prepared pizza dough into a round (about 12 inches in diameter) place onto a lightly greased pizza pan. Place slices of Swiss cheese on the dough, leaving a 1-inch border for the crust. Distribute the caramelized onion mixture evenly over the cheese slices. Sprinkle with grated Gruyere and Parmesan and bake for 20 minutes.

Step 5

Remove from oven and sprinkle with chopped parsley and thyme sprigs, if desired. Cool 5-10 minutes before slicing.