I got this recipe long ago from a magazine and found that it was delicious with a few tweaks. Use fat reduced cheeses to cut calories if desired. It is easy and quick which makes it good on those busy weeknights. The squash can also be baked in the oven by cutting into halves (remove seeds) and placing them upside down on a baking sheet and baking for 45 min or until soft. The left-overs are good too, but don't try to keep them too long.
Poke holes in squash with a knife so steam can escape. Microwave on high for 5 minutes; flip over, microwave another 5 minutes or until soft. Let stand 5 minutes.
Cut into halves and discard seeds. Scrape inside of squash to make "spaghetti" strings. Set one of the shell halves aside. Toss strings with the rest of the ingredients. Place the mixture into saved shell half.
Heat in microwave on high for 2 minutes to warm through. Serve.