In a large bowl, combine the broccoli, cauliflower, shredded cheese, heavy cream, garlic powder, and onion powder. Season with salt and pepper to taste.
Transfer the mixture to a baking dish and spread it out evenly.
Bake in the preheated oven for 30 minutes, or until the vegetables are tender and the top is golden brown.
Let it cool for a few minutes before serving. Enjoy!
Notes:
This casserole is great for meal prep and can be stored in the fridge for up to 3 days.