Preheat the broiler to high.

Melt the butter in a large soup pot over medium-high heat. Add the onions, garlic and brown sugar and cook about 10 minutes, stirring frequently, until softened. Continue cooking, stirring often, until the onions are deep golden in color and caramelized, 15 minutes.

Reduce the heat to low and sprinkle the flour over the onions, stirring the flour into the onions. Cook for 5 minutes, until the raw flour taste is eliminated. Add the wine, beef broth, Worcestershire sauce, bay leaves, and thyme. Increase the heat to medium-high and return the soup to a simmer. Stir in the gnocchi and cook until the gnocchi floats, 5 minutes. Remove the thyme sprigs and bay leaves from the soup. Season, to taste with salt and pepper.

Ladle the soup into oven safe bowls and top evenly with cheese. Place each soup bowl on a baking sheet and transfer to the oven, broil until bubbly and golden brown, 3 to 5 minutes. Eat!