- Preheat Oven & Prepare Dish:
Set your oven to 375°F (190°C). Lightly grease a 9×13-inch casserole dish (or two 8×8 pans) with non-stick spray and set aside. - Cook the Spaghetti:
Boil the pasta for 6 minutes only—it should be quite firm since it will continue cooking in the oven. Drain and set aside. - Make the Roux:
In a large pot or Dutch oven, melt the butter over medium heat. Add the flour and whisk constantly for about 30 seconds to create a smooth roux and eliminate the raw flour taste. - Season the Base:
Stir in the salt, black pepper, garlic powder, and cayenne, whisking to incorporate the spices evenly into the roux. - Build the Sauce:
Slowly add the half-and-half and heavy cream, whisking continuously until smooth. Bring to a gentle boil, then reduce heat and stir in half of the mozzarella and cheddar cheeses. Continue stirring until the cheese is fully melted and the sauce is velvety. - Add Pasta to Sauce:
Turn off the heat. Toss the drained spaghetti directly into the cheese sauce, stirring until the noodles are evenly coated. - Assemble the Dish:
Spoon the cheesy pasta into your prepared baking dish, spreading it into an even layer. Sprinkle the remaining mozzarella and cheddar cheeses generously on top. - Bake to Finish:
Place in the oven and bake for 25–30 minutes, or until the edges are bubbling and the top layer of cheese is golden and melted to perfection.
ADVERTISEMENT