01 -
Preheat oven to 350°F (175°C). Bring a large pot of salted water to a boil. Cook pasta shells until al dente according to package instructions. Drain and set aside.
02 -
In a large skillet over medium heat, cook chopped bacon until crisp. Transfer bacon to paper towels to remove excess grease.
03 -
In the same skillet, melt unsalted butter over medium heat. Whisk in flour, cooking for 2-3 minutes until golden. Gradually whisk in whole milk, stirring until smooth and slightly thickened. Stir in shredded cheddar and mozzarella cheeses until fully melted.
04 -
Mix cooked pasta shells and crumbled bacon into the cheese sauce until evenly coated.
05 -
Transfer mixture to a greased 9x13-inch baking dish. Toss panko breadcrumbs with melted unsalted butter and sprinkle evenly over the top. Bake for 20 minutes or until golden brown and bubbling.