Preheat oven to 350° F.
Place bread crumbs, melted butter, two Tablespoons Parmesan cheese, garlic powder, onion powder and parsley in a small bowl, and stir to combine. Set aside.
Spray a large skillet with non-stick spray. Add chopped onions and cook on medium heat until softened and golden brown, stirring often. Stir flour into onions, and then add milk to skillet. Give it a good stir; the sauce will begin to thicken as it cooks. Once sauce begins to thicken, add remaining grated Parmesan cheese and cream cheese (cut cream cheese into chunks- it will melt faster). Continue to cook, stirring often, until all the cream cheese has melted.
Add broccoli and cauliflower florets to the sauce; stir to fully coat veggies with sauce. TIP: At this point, I recommend taste-testing the sauce. Season with a little garlic powder, salt and pepper, to suit your personal taste buds!
Spray a 2 quart baking dish with non-stick spray. Pour veggies and sauce into dish. Top the dish with the reserved bread crumb mixture. Bake at 350° F for 45 minutes, until top is golden brown, and sauce is bubbling around the edges. Let cool for a couple minutes, then serve and enjoy!
Broccoli Cauliflower Bake https://www.thegratefulgirlcooks.com/broccoli-cauliflower-bake/