In a covered large nonstick skillet cook potatoes in a small amount of boiling water for 5 minutes. Add asparagus. Cook, covered, for 5 to 7 minutes more or until vegetables are tender. Drain vegetables in a colander. Cool and dry the skillet. Lightly coat the skillet with nonstick cooking spray. Return vegetables to the skillet.
In a small bowl combine eggs, parsley, rosemary, onion powder, salt, and pepper. Pour over vegetables in the skillet; do not stir. Cook over medium heat. As mixture sets, run a spatula around the edge of the skillet, lifting egg mixture so that the uncooked portion flows underneath. Continue cooking and lifting edge until egg mixture is nearly set (top will be moist).
Remove skillet from heat. Let stand, covered, for 3 to 4 minutes or until top is set. Sprinkle with tomatoes and Parmesan cheese. Makes 4 (about 1-cup) servings.