Preheat the oven to 350 degrees. Add 8-10 cups of water to a large stock pot. Place it over medium high heat to bring it to a boil. Add 1-2 teaspoons of salt to flavor the water. Once the water begins to boil, add the Pennone pasta. Boil over medium high for 10 minutes, check the pasta by removing one piece. Pasta is done when it is al dente.

Drain the water and run cold water of the pasta so that it stops the cooking process.

Add the mild italian sausage to a skillet that is over medium heat. Cook the sausage and begin crumbling it up with a spatula or spoon. Cook for 8-10 minutes, or until it is no longer pink.

After the meat is thoroughly cooked, add the marinara sauce to the skillet. Simmer the sauce on low for 5 minutes. Once it begins to bubble, add the spinach and stir it in thoroughly. Remove the skillet from the heat and set aside.

Pour a small amount of the marinara sauce to a pre-greased 9x13 baking dish.

In a medium size bowl, combine the ricotta cheese, basil, and thyme. Mix well. Add the cheese mixture to a small ziploc bag. Cut a small slit in one end of the bag.

Begin filling the cooked pasta with the ricotta cheese mixture. Place one layer of the filled pasta into the baking dish. Cover with some of the marinara sauce and sprinkle with mozzarella cheese.

Continue layering the pasta. On the final layer, add the remaining marinara sauce, and cover with mozzarella cheese. Sprinkle chopped basil on top.

Cover with foil and bake in the oven for 20 minutes.