Heat the olive oil in a large skillet, add the diced onions, cook 3-4 minutes then add the garlic and cook for an additional minute.
Add the sausage and cook through.
Add the red wine, tomato paste, diced tomatoes, tomato sauce and Italian seasoning.
Reduce to low, cover and simmer 20-30 minutes.
Three Cheese Manicotti
Preheat the oven to 350°F.
Bring a large pot of water to boil.
Add the manicotti shells and cook 4-5 minutes, drain, then set aside in an even layer on a cutting board to cool.
In a medium bowl, combine the ricotta cheese, 1 cup mozzarella cheese, parmesan cheese, fresh basil, parsley and oregano.
Place this mixture in a piping bag, or ziploc bag with a cut corner.
Pipe the cheese mixture into the manicotti shells.
Pour half of the Italian Sausage Marinara in a 9 inch x 13 inch baking dish.
Place the filled manicotti shells in a single layer on top of the sauce.
Pour the remaining sauce over the shells.
Top with the remaining cup of mozzarella cheese.
Place in the oven and bake for 20-25 minutes.
Notes
Freezing Manicotti: before baking this manicotti recipe, it can be frozen in an airtight container for up to 6 months. To defrost the manicotti, place it in the refrigerator for 24 hours, then bake at 350°F for 25-30 minutes.
Vegetarian Manicotti: to make this recipe vegetarian, omit the sausage from the marinara sauce. Two cups of diced zucchini or finely chopped cauliflower can be added in it's place, if desired. Also be sure to use vegetarian parmesan-style cheese instead of traditional parmesan in the cheese filling.