Cheese Stuffed Pasta Shells

Boil a substantial quantity of salted water in a large vessel until it reaches a rolling boil. Submerge pasta shells in the boiling water, periodically stirring to ensure even cooking, until they are fully cooked but still retain a slight firmness in the center, approximately 8 minutes. Drain excess water.

Heat a generous amount of olive oil in a large skillet over medium-high heat. Sauté sliced mushrooms and minced garlic in the hot oil until they become tender, about 7 minutes. Introduce fresh spinach leaves and dried thyme into the mushroom mixture; season with salt and pepper to taste. Continue cooking the mixture until the spinach has wilted, then remove it from the heat source and discard any excess moisture. Transfer the cooked mixture to a spacious bowl.

Preheat your oven to 375 degrees Fahrenheit (190 degrees Celsius).

Mix together ricotta cheese, 3/4 cup of shredded mozzarella cheese, and 1/2 cup of grated Parmesan cheese with the spinach mixture. Re-season with salt and pepper to taste, then fill pasta shells with this mixture.

Arrange the stuffed pasta shells in a 9x11-inch baking dish. Pour a generous amount of pasta sauce over the shells, followed by 1/4 cup of shredded mozzarella cheese and 1/4 cup of grated Parmesan cheese.

Bake the stuffed shells in the preheated oven until the cheese is melted and the shells are hot, approximately 30 minutes.