Place the chicken in the oven and bake at 425 for 30-35 minutes until it reaches an internal temperature of 165F
Meanwhile, add oil to a saute pan on medium high heat. Saute the onions, mushrooms, and garlic until they soften.
Then, add butter and flour to make a roux (paste). Stir until it is completely mixed.
Next, add heavy cream and the rest of the garlic powder, onion powder, and salt.
Simmer until it thickens into half the amount. Then, add the green beans and mix well.
Place the green beans in a baking dish that has been greased. Top it off with the shredded cheddar cheese.
Bake in the oven for 15-20 minutes.
Carefully remove from the oven once all items have cooked. Eat and enjoy!