In a saucepan, melt butter over medium heat.
Whisk in flour to make a roux. Cook for 1 minute.
Gradually whisk in milk until smooth and slightly thickened.
Add shredded cheese (reserve some for topping) and stir until melted.
Season with garlic powder, herbs, salt, and pepper.
Combine pasta and sauce in a large bowl, mixing well.
Transfer to casserole dish and spread evenly.
Top with cheese & breadcrumbs for a crispy finish.
Bake for 20–25 minutes, until golden and bubbly.
Serve hot as a main or side dish.