• Position the oven rack in the bottom third of the oven and preheat the oven to 400 degrees. Lightly grease a 6-cup soufflé dish with 1 tablespoon butter and sprinkle the sides and bottom with a thin layer of bread crumbs. Tap out any excess crumbs.
• Place the pancetta in a large saucepan over medium-low heat. When the pancetta has rendered a few tablespoons of fat, increase the heat to medium-high. Cook until crisp, stirring regularly to prevent sticking. Remove the pancetta and discard all of the bacon fat.
• Melt the remaining 3 tablespoons of butter in the same saucepan. When the butter has melted, add the onions and sauté until soft and slightly brown, about 10 to 15 minutes. Remove the pan from the heat and add the flour to create a roux. Return the roux to the heat and cook a few minutes, stirring regularly, until it is the color of straw, about 2 to 3 minutes. Gradually add the warm milk, whisking well until quite thick and smooth.
• After the mixture comes to a boil, remove the pan from the heat, cool slightly and whisk in the egg yolks one at a time. Add the grated Gruyère and 4 tablespoons of the Parmesan cheese. Mix well. Season with salt and pepper.
• Place the egg whites in the bowl of an electric mixer fitted with a whip attachment. Beat the whites on medium-high speed until they are stiff but not dry.
• Mix a quarter of the whipped egg whites into the yolk-cheese base, then gently fold in the remaining egg whites, thyme and reserved pancetta. Working quickly, spoon the mixture into the soufflé dish. Smooth the surface with a small offset spatula and sprinkle with the remaining 2 tablespoons of Parmesan cheese. (Avoid pouring or over-folding the soufflé mixture, as excessive handling can deflate the egg whites.)
• So that the top of the soufflé rises like a top hat, draw your index finger around the perimeter of the dish about 1 inch from the side to create a shallow channel in the soufflé surface.
• Reduce the oven temperature to 375 degrees and bake the soufflé about 40 to 45 minutes until a skewer inserted deep into the side of the soufflé comes out clean. The top should be golden brown and firm to the touch. Serve immediately.
1 to 2 Tbsp. plain bread crumbs
¼ lb. pancetta, diced
½ cup diced yellow onion
3 Tbsp. all-purpose flour
1 cup milk, warmed
4 large egg yolks
5 large egg whites
2/3 cup finely grated Gruyère cheese
6 Tbsp. finely grated Parmesan cheese, divided
1½ Tbsp. finely chopped fresh thyme
Salt and freshly ground black pepper to taste
This article appears in Feb 1-28, 2007.