Slice the squash lengthwise and scoop out seeds.
Place squash, cut side down, in a baking dish.
Add water and cover tightly with foil.
Bake at 375° for 20-30 minutes or until easily pierced with a fork.
Meanwhile, brown beef in a large skillet; drain.
Add onion, green pepper, herbs and seasonings; saute until onion is transparent.
Stir in tomato puree.
Cover and cook over low heat, stirring occasionally.
Scoop out the squash, separating the strands with a fork.
Just before serving; stir 1/2 cup Parmesan cheese into the meat sauce.
Serve sauce over spaghetti squash and pass remaining Parmesan.