• Jumbo pasta shells: 20, cooked according to package instructions
• Ricotta cheese: 1 cup, creamy base for the filling
• Grated Parmesan cheese: 1/2 cup, for a sharp, nutty flavor
• Cooked mushrooms: 1 cup, finely chopped
• Egg: 1, beaten, to bind the filling
• Garlic powder: 1 teaspoon, for a subtle garlic flavor
• Salt: 1/2 teaspoon, to season
• Black pepper: 1/2 teaspoon, for a touch of spice
• Alfredo sauce: 2 cups, divided (1 cup for the base and 1 cup on top)
• Shredded mozzarella cheese: 1/4 cup, to melt on top