Gluten Free Green Bean Casserole

Name: Gluten Free Green Bean Casserole
Ingredients: 3 sweet onions, halved and thinly sliced; 2 cups unsweetened soy or almond milk; 2 cups gluten free flour; 1 tsp garlic powder; Salt and pepper; Oil for frying; 4 cups fresh green beans, ends cut off, cut in half; 2 tablespoons oil (use a high smoke point oil like coconut or grapeseed); 1 small onion, finely chopped; 3 cloves garlic, minced; 1 cup mushrooms, finely chopped; 4 cups creamy mushroom soup (I use Imagine brand Creamy Portobello); 1/4 cup cornstarch; 1/4 cup nutritional yeast (optional); 2 Tbsp vegetable stock concentrate; 2 Tbsp mellow white miso paste; 1 cup vegan sour cream; Salt and pepper to taste