Cook Pasta & Broccoli:

Preheat oven to 375°F (190°C).

Cook pasta in a large pot of salted boiling water until al dente. In the last 2 minutes, add broccoli to the pot.

Drain and set aside.

Make the Cheese Sauce:

In a saucepan, melt butter over medium heat. Whisk in flour and cook for 1–2 minutes to form a roux.

Slowly whisk in milk and chicken broth. Stir until thickened (3–4 minutes).

Add garlic powder, salt, and pepper. Stir in cheddar and Parmesan cheeses until melted and smooth.

Combine Everything:

In a large bowl or pot, mix the cooked pasta, broccoli, chicken, and cheese sauce until evenly coated.

Pour into a greased 9x13-inch baking dish.

Add Topping & Bake:

(Optional) In a small bowl, mix breadcrumbs with melted butter and sprinkle over the top.

Bake uncovered for 20–25 minutes, or until bubbly and golden.

Serve:

Let rest for 5–10 minutes before serving. Garnish with extra Parmesan or chopped parsley if desired.