Cook manicotti according to package directions, omitting salt and fat.

Preheat oven to 350°F.

Heat a large nonstick skillet over medium-high heat.

Coat the skillet with cooking spray.

Remove casings from sausage.

Add sausage to the pan; cook for 5 minutes or until browned, stirring to crumble.

Add onion and bell pepper to the pan; sauté for 5 minutes or until tender.

Melt butter in a medium saucepan over medium heat.

Stir in flour and cook for 2 minutes, stirring constantly with a whisk.

Remove from heat and gradually add milk, stirring with a whisk.

Return the pan to heat and bring to a boil.

Cook for 6 minutes or until thickened, stirring constantly with a whisk.

Remove from heat and stir in black pepper.

Add 1/2 cup of the milk mixture to the sausage mixture and stir well.

Spoon about 1/3 cup of the sausage mixture into each manicotti.

Arrange the manicotti in a single layer in a 13x9" baking dish coated with cooking spray.

Sprinkle mozzarella over the manicotti.

Spread the remaining sausage mixture evenly over the mozzarella.

Top the sausage mixture with pasta sauce, spreading to cover.

Sprinkle with Parmesan cheese.

Bake at 350°F for 35 minutes or until bubbly.