Preheat oven to 375
Bring large pot of water to a boil
Trim and cut green beans into thirds
Add beans to boiling water, once it returns to a boil set 5 minute timer
Chop 1/2 an onion and all of the mushrooms and place them in a non-stick suace pan
Once mixture is softened add salt, milk, broth, and coconut aminos and simmer at low heat for 7 minutes
Grab a small pot for the topping and add in avocado oil, 1 onion chopped into large pieces and bread crumbs. Toss until brown.
Coat a casserole dish with nonstick spray and pour in green beans and mushroom sauce. Top with onion crumble.
Cook in the oven for 30 minutes.