|Eggs||8 Small, separated|
|Asparagus||1 Pound, cut diagonally into 1 1/2 inch pieces|
|Small mushrooms||1⁄2 Pound, each cut into quarters|
|Onions||2 Medium, thinly sliced|
|Canned tomatoes||8 1⁄4 Ounce (1 Can)|
1. Preheat oven to 350°F. In large bowl, with mixer at high speed, beat egg whites until stiff peaks form. In small bowl, with same beaters and with mixer at high speed, beat egg yolks, 1/4 cup water, 1/2 teaspoon salt, 1/2 teaspoon thyme, and 1/8 teaspoon pepper until very thick. With wire whisk or rubber spatula, gently fold egg-yolk mixture into beaten egg whites.
2. In 12-inch oven-safe skillet over medium-low heat, melt 2 tablespoons butter or margarine (1/4 stick); add egg mixture and cook until top is puffy and bottom is golden when gently lifted with a pancake turner, about 3 minutes.
3. Place skillet in oven. Bake until top of omelet is golden and springs back when lightly touched with finger, about 10 minutes.
4. Meanwhile, in 10-inch skillet over medium heat, melt 2 tablespoons butter or margarine (1/4 stick); add asparagus, mushrooms, onions, 3/4 teaspoon salt, 1/2 teaspoon thyme, and 1/8 tea spoon pepper and cook until vegetables are tender-crisp, about 5 minutes, stirring frequently. Stir in tomatoes with their liquid, and sugar. In cup, stir cornstarch and 1 tablespoon water until blended; stir into vegetable mixture. Cook over medium heat, stirring constantly, until mixture thickens slightly.
5. To serve, loosen side and bottom of omelet from skillet; spoon half of vegetable mixture over half of omelet; fold omelet over vegetables. Tilt skillet; with pancake turner, gently slide omelet onto warm platter. Spoon remaining vegetable mixture around omelet.