• Preheat oven to 400 degrees F (204 C) and lightly grease 9×13 baking dish.

Make the Crispy “Fried” Onions

• Add 1 tablespoon of butter to a large skillet. Once melted, add the sliced onion and sauté for 4 to 6 minutes or until the onions and started to become lightly golden brown and tender.
• Transfer the onions to a mixing bowl and then add the breadcrumbs, nutritional yeast, garlic powder, paprika, salt, and pepper. Toss until everything is combined and the onions are well coated in the breadcrumbs.

Blanch the Green Beans

• Bring a large pot of water to a boil and salt well - it will help season the green beans. Add green beans and cook for 5 minutes, then drain and place in an ice water bath to stop cooking. Drain and set aside.

Make the Mushroom Sauce

• In a large skillet over medium heat, add olive oil and shallots and garlic. Season with salt and pepper and stir. Cook for 2-3 minutes.
• Add mushrooms and season with a bit more salt and pepper. Cook for 3-4 minutes more or until lightly browned.
• Sprinkle in flour and whisk to stir and coat the veggies. Cook for 1 minute, then slowly add in veggie stock, whisking to incorporate.
• Add almond milk next and whisk to stir again. Season with a touch more salt and pepper and bring to a simmer, then reduce heat to low to thicken. Cook for 5-7 minutes more, or until thick and bubbly. Taste and adjust seasonings as needed.

Assemble the Casserole

• Pour the sauce evenly over the green beans in the casserole dish. Stir gently to ensure that everything is well combined and the green beans are evenly coated with sauce.
• Add 1/3 of the "fried" onions and all of the cooked green beans. Toss to coat well, and top with remaining fried onions.
• Bake for 15 minutes, or until warmed through and bubbly and slightly browned on top. Serve immediately (handle pan carefully).
• Leftovers store well in the fridge for for 3-4 days.