Add the onions and garlic, along with a little water, to a large pan and saute over medium heat until they start to caramelize, being careful not to burn them. When they have caramelized a little, remove them from the heat and set aside.
Using a steamer, steam the green beans over 1″ water until tender, about 5 minutes. Add the green beans to one half of the onion/garlic mixture in a large bowl.
Using the same pan as you cooked the onions in, saute the garlic for a minute and then add the chopped mushrooms. They should give off enough water to keep them from sticking, but you can add more water if they stick.
Add the Tamari, thyme, salt & pepper and saute until lightly browned.
In a small jar or bowl, add the whole wheat flour and 1/4 cup water or vegetable broth. Whisk or cover and shake until well blended.
Add the non-dairy milk to the mushrooms along with the flour mixture and stir continuously. Add the vegetable broth, nutmeg, salt, and pepper and continue to stir until the sauce thickens. Check for flavor and add salt & pepper as needed.
Once the sauce has thickened, removed it from the heat.
Place the green beans (mixed with the onions) in a 2-quart casserole dish. Pour the mushroom sauce over the green beans and spread it around to get into every nook and cranny.
Sprinkle the other half of the caramelized onions over the green bean/sauce mixture and top with the breadcrumbs.
Cover and bake for 20 minutes. Removed from the heat and sprinkle the sliced almonds over the top. Return to the oven and continue to cook for about another 10 minutes until the sauce is bubbly. Check to make sure the almonds aren’t burning.