Preheat oven to 450 degrees. Brush 1 TBS butter onto the sides, bottom, and corners of an 8 x 8 baking dish.
In a large pot of boiling water, steam broccoli for 5 minutes and drain. Place drained broccoli into prepared 8 x 8 baking dish.
In a small skillet heat 1 TBS butter. Stir in bread crumbs for a few minutes until toasty. Turn off heat and remove from burner.
In medium sauce pan over medium heat melt 3 TBS butter. Add in flour and whisk for 1 minute. Gradually whisk in milk and season with salt, black pepper, garlic powder, and onion powder. Give a taste to adjust seasonings, if needed. Allow to simmer a few minutes until thickened.
Sprinkle 4oz cheddar cheese evenly over broccoli. Pour white sauce over cheese. Sprinkle with remaining 4oz cheddar cheese. Top with toasted bread crumbs.
Bake in preheated oven for 20 minutes.