Cook the tortellini in plenty of boiling salted water for 13-17 minutes. Clean, wash and cut the peppers into strips. Cut cheese into cubes. Roast sunflower seeds in a pan without fat, remove and let cool on a plate. Mix mayonnaise, yoghurt and pesto.
Season with salt and pepper. Drain the tortellini and leave to drain well. Mix the pasta, peppers and cheese with the salad dressing. Sprinkle with sunflower seeds and garnish with basil if desired