Prep your tools. Preheat the oven to 400 degrees F and bring a large pot of water to boil. Grease your baking dish with 2 tablespoons of the butter. Set aside.

Cook the veggies. Heat the oil in a large skillet and saute the onion until translucent, about 4 minutes. Add the garlic, zucchini, mushrooms, celery, salt and pepper. Continue cooking over medium-high heat for about 5 minutes, stirring constantly, until the vegetables have softened.

Finish the sauce. Add the tomatoes, thyme, sage and red wine. Cook uncovered over medium-high heat until the liquid has reduced by half. Remove from the heat and set aside. (A good way to judge whether the liquid has reduced by half is to stick the handle end of a wooden spoon into the pot just after the wine has been added. Now you have a visual measurement of how much liquid there was at the beginning. The mixture is done when the handle measures half of the original height.)

Cook the pasta. When the water has come to a boil add a generous dash or two of salt. Cook the rigatoni according to the package instructions. Drain the pasta, add it to the casserole dish, then add the cooked vegetables. Mix well.

Add some mozzarella. Sprinkle 2 cups of the mozzarella in with the pasta and mix well.

Make the creamy sauce. Whisk the Parmesan cheese with the cream and eggs, add the sage, and season with a pinch of salt and pepper. Pour the sauce over the pasta and vegetables.

Add the rest of the mozzarella. Sprinkle the remaining 1/2 cup of mozzarella over the pasta.

Bake the pasta and add butter. Bake for 15 minutes. Melt the remaining 2 tablespoons of butter and drizzle the melted butter over the pasta. Bake for another 10 to 15 minutes, until the cheese has melted and the pasta is bubbly. Allow the pasta to cool and set for 5 to 10 minutes before serving.