Creating Creamy Vegan Broccoli Casserole is simple when you follow these steps:

1. Preheat the Oven: Preheat your oven to 350°F (175°C).
2. Cook Broccoli: Steam the broccoli florets for about 5 minutes until they are bright green and slightly tender. Drain and set aside.
3. Sauté Onions and Garlic: In a pan, heat olive oil over medium heat. Add chopped onions and sauté until translucent, about 5 minutes. Add minced garlic and cook for an additional minute.
4. Make the Creamy Sauce: In a mixing bowl, combine almond milk, nutritional yeast, cashew cream, onion powder, garlic powder, salt, and black pepper. Whisk until smooth.
5. Combine Ingredients: In a large bowl, mix the steamed broccoli, cooked quinoa, sautéed onions and garlic, and the creamy sauce. Stir until everything is well coated.
6. Transfer to Baking Dish: Pour the mixture into a greased 9×13-inch baking dish. Spread it evenly.
7. Add Breadcrumbs: If using, sprinkle the breadcrumbs over the top for added crunch.
8. Bake: Place the casserole in the preheated oven and bake for 25-30 minutes, until heated through and the top is golden brown.
9. Garnish: Remove from the oven and let it cool for a few minutes. Garnish with fresh parsley if desired.

This step-by-step process will guide you in creating this incredible casserole effortlessly.