Bring a large pot of salted water to a boil. Add pasta and cook until al dente, about 8-10 minutes. Drain and reserve a cup of pasta water.

In the same pot, bring water to a boil and steam the broccoli for about 3-4 minutes until tender yet crisp. Drain and set aside.

In a saucepan over medium heat, melt butter. Whisk in flour to form a roux for about a minute until golden. Gradually add milk and cook until thickened, about 4-5 minutes.

Reduce heat to low, mix in cheddar and cream cheese until melted. Season with garlic powder, salt, and pepper.

Fold in pasta and steamed broccoli, adding reserved pasta water if needed to reach desired consistency. Warm through for 2-3 minutes.

Serve hot, garnished with additional cheddar or black pepper if desired.