1 tablespoon extra-virgin olive oil
4 sweet Italian pork or turkey sausages (12 ounces), casings removed
One 24-ounce jar marinara sauce
1/2 cup water
Two 14-ounce packages fresh cheese ravioli
One 14-ounce package fresh spinach-and-cheese ravioli
12 ounces shredded mozzarella cheese (3 cups)
3 tablespoons freshly grated Parmesan cheese
1 1/2 pounds mixed roasted or grilled vegetables, cut into 1-inch pieces
Preheat the oven to 375°. Bring a large pot of salted water to a boil. In a large saucepan, heat the olive oil until shimmering. Add the sausage meat and cook over moderately high heat, stirring and breaking up the lumps with a wooden spoon, until no longer pink, about 5 minutes. Add the marinara sauce and the water and simmer for 5 minutes.
Add the packages of fresh ravioli to the boiling water and cook until al dente. Drain the ravioli and return them to the pot. Add the sausage marinara and toss gently with the ravioli to coat.
Spoon one-third of the ravioli and sauce into a 3-quart baking dish in an even layer. Sprinkle with 1 cup of the shredded mozzarella and 1 tablespoon of the Parmesan. Layer another one-third of the ravioli on top, followed by all of the vegetables, 1 cup of mozzarella and 1 tablespoon of Parmesan. Top with the remaining ravioli, spooning on any remaining sauce and sausage. Sprinkle the remaining 1 cup of mozzarella and 1 tablespoon of Parmesan on top and cover with foil.
Bake the ravioli lasagna for 30 minutes, until bubbling. Uncover and bake for 25 minutes longer, until lightly browned and bubbling. Let the lasagna stand for 10 minutes before serving.
Make Ahead: The recipe can be prepared through Step 3 and refrigerated overnight. The baked lasagna can be refrigerated for up to 3 days.