Set a large oven-safe skillet or shallow dutch oven over moderate heat with the butter. Once melted and hot, add in the sliced onions. Season with a large pinch of salt, pepper, fresh thyme leaves and bay leaf. Cook until deeply golden brown and caramelized, about 25 minutes. Make sure to stir often so that the onions don't burn.

Stir in the gnocchi, no need to boil, and cook for a few minutes to lightly brown them. Deglaze the pan with the wine and cook until almost evaporated. Stir in the beef broth and bring to a simmer. Cook until the gnocchi has softened, about 10 to 15 minutes.

Meanwhile, arrange the baguette slices on a baking sheet and drizzle with the olive oil. Pop under a preheated broiler until golden brown and crispy. Season with a bit of salt and set aside.

Remove the gnocchi from the heat, discard the bay leaf and sprinkle the top evenly with cheese. Pop under the broiler to melt and brown the top. Remove from the oven and garnish with fresh thyme leaves. Serve with the toasted bread slices and enjoy!