2 drops lemon juice or 1/8 teaspoon cream of tartar
1/4 teaspoon kosher salt
Confectioner’s sugar for dusting
For Caramel Sauce:
Combine sugar, corn syrup, lemon juice and water in a saucepan and bring to boil. Caramelize sugar mixture, stirring until mixture is dark amber colored. Turn off heat; add butter and stir to melt.
Add cream slowly. When all cream is added, stir just once around. Add 1/4 cup Emmi Kaltbach Le Gruyère cheese. Allow mixture to steep about 30 minutes. Stir to blend. Strain through a mesh strainer. Salt to taste.
For Soufflé: Heat oven to 400°F.
Butter 1 quart soufflé dish; grate a little Kaltbach Le Gruyère cheese all around the sides. Dust with Ovaltine® or sugar.
Combine chocolates in bowl positioned over a simmering pot of water to melt. Do not immerse bowl bottom in the hot water. Combine 1 tablespoon milk with cornstarch and cocoa powder; stir until smooth.
Heat remaining 1/2 cup milk in saucepan; bring just to a boil.
Meanwhile, whisk egg yolks and half the sugar together in a bowl. Add the cocoa-cornstarch mixture to yolks and whisk together. Add a little of hot milk to the egg yolk mixture; whisk.
Pour mixture back into the pot with hot milk and whisk. Return to heat set at medium; whisk continuously until it starts to boil and become very thick similar to pastry cream.
Add this mixture to melted chocolate, folding until well combined. In a standing mixer bowl, combine egg whites with lemon juice and salt. Whip until foamy; add a little of remaining sugar.
Continue to whip, gradually adding remaining sugar to form stiff peaks.
Gently fold egg whites into chocolate mixture along with remaining grated Le Gruyère cheese. Pour mixture into prepared soufflé dish and place on middle oven rack; bake about 20 minutes or until soufflé has risen about 1 inch above dish rim and is set around edges.
Remove soufflé from oven and dust with confectioner’s sugar. Place on serving plate immediately.
At the table, make a slit with a spoon in the middle of soufflé and pour room temperature Le Gruyère caramel sauce into the opening. Spoon servings out onto plates or bowls with additional caramel sauce on the side.