Ingredients
Equipment
Method
Cook the shells
- Heat the oven to 375°F.
- Bring water to a boil in an 8-quart pot, add the 1 tablespoon kosher salt and pasta shells, and cook 1 minute less than the package directions; drain.
Make the filling
- Heat the olive oil in a 12-inch skillet over medium heat, add the finely chopped cremini mushrooms, and cook for 7 to 9 minutes, stirring occasionally, until browned and their liquid has evaporated.
- Stir in the minced garlic and cook for 30 seconds.
- Add the baby spinach in handfuls and stir until wilted, about 2 to 3 minutes.
- Transfer the mushroom mixture to a medium bowl and let it cool for 10 minutes, until just warm.
- Mix in the whole-milk ricotta, large egg, 1 1/2 cups of the shredded low-moisture mozzarella, 1/2 cup of the grated Parmesan, 1/2 teaspoon kosher salt, and 1/4 teaspoon black pepper.
Assemble and bake
- Spread 1 cup of the marinara sauce in a 9x13-inch baking dish.
- Fill the shells with the ricotta mixture.
- Arrange the filled shells in the dish.
- Spoon the remaining marinara sauce over the shells and sprinkle with the remaining 1/2 cup mozzarella and 1/4 cup Parmesan.
- Cover the dish tightly with foil and bake for 25 minutes.
- Uncover and bake for 10 to 15 minutes, until bubbling and the center of the filling reaches 160°F.
- Let the shells rest for 10 minutes before serving.
Notes
Let the mushroom mixture cool until just warm before mixing it with the ricotta and egg. Refrigerate leftovers for 3 to 4 days; freezer: yes. For a gluten-free option, use gluten-free jumbo shells if available.
