Preheat oven 350 degrees. Mix bread crumbs with 2 tbsp parmesan cheese and 2 tbsp melted butter. Add the italian seasoning. Set aside. Cut up any large pieces of broccoli and cauliflower.
Melt two tbsp butter in large skillet. Saute the onion until tender. Stir in flour, garlic powder, salt and pepper. Add milk and cook until thickened and bubbly. Add the 1/4 cup parmesan cheese and cream cheese. Cook until cheese is melted.
Add the broccoli and cauliflower and stir to combine. Place in baking dish. Top with bread crumb mixture and bake about 40 minutes.