Mix together the oil, garlic and bread crumbs and spread on a large plate. Cook in microwave for 4-5 minutes on HIGH power. Stir every minute until crisp and beginning to brown; set aside.
Dice the squash. Place in a large bowl with half of the water. Cover and cook on HIGH for 8-9 minutes, stirring occasionally; leave to stand for 2 minutes.
Place the pasta in a large bowl. Add a little salt and pour boiling water to cover by 1 inch over. Cover and cook on HIGH for 5 minutes, stirring once, until the pasta is just tender, but still firm to the bite. Leave to stand, covered, for 1 minute before draining. (Feel free to sub dry pasta and cook it traditionally).
Place the butter and onion in a large bowl. Cover and cook on HIGH power for 3 minutes.
Coarsley mash the squash. Add to the onion with the pasta, ham, cream, cheese, parsley and remaining water; season generously to taste and mix well. Cover and cook on HIGH for 4 minutes until heated through.
Serve the pasta sprinkled with the crisp garlic crumbs.