Whisk eggs with pesto and sun-dried tomatoes in a small bowl. Preheat a small non stick skillet to medium, spray with cooking spray. Pour egg mixture into skillet. As mixture sets at the edges, with spatula, gently lift cooked portion to allow uncooked egg to flow underneath. Cook until bottom is set and top is almost set, about 5 minutes. Sprinkle swiss cheese on half of the omelette. Place tomato slices on the cheese. Sprinkle with nuts or seeds. Fold gently in half. Serve immediately on warm plate.