Wild Mushroom and Fontina Cheese Omelettes

Melt 3 tablespoons butter in heavy large skillet over high heat. Add mushrooms and onion; saute until golden brown, about 15 minutes. Mix in Sherry; cook 1 minute. Remove from heat. Mix in sour cream and thyme. Season to taste with salt and pepper. Set aside

Whisk eggs, salt and pepper in large bowl to blend.

Melt 1 teaspoon butter in 7-inch nonstick omelette pan over medium-low heat. Pour generous 1/2 cup egg mixture into pan and cook until almost set, tilting pan and lifting egg mixture with rubber spatula to allow uncooked portion to run underneath, about 1 minute. Spoon 1/3 cup mushroom mixture over half of omelette. Sprinkle mushrooms with about 3 tablespoons cheese. Cover and cook until cheese melts, about 2 minutes. Fold unfilled half of omelette over filling. Slide omelette out onto plate. Repeat with remaining butter, egg mixture, mushroom filling and cheese, forming total of 6 omelettes.