Boil Pasta in salted water, strain and set aside. In a bowl toss in the Pesto, salt, the Feta Cheese diced into cubes, and diced Zucchini. Mix ingredients, add into your pasta. In a medium size buttered baking pan, add in the pasta mixture, and spread. Then take a medium size sauce pan, add in the butter stir until melted, add the flour continue to stir, slowly add in the milk, nutmeg and stir until it has become one thick sauce.