Healthy Green Bean Casserole

INGREDIENTS

1/2 cup

whole wheat panko breadcrumbs

1/4 cup

freshly grated Parmesan cheese

2 tbsp

chopped fresh parsley (plus additional for garnish)

4 tbsp

extra-virgin olive oil (divided)

2 1/2 lb

green beans (trimmed)

medium onion (very thinly sliced)

8 oz

baby bella (cremini) mushrooms (sliced (do not use plain white mushrooms, as they do not have much flavor))

3 tbsp

all-purpose flour

2 cups

2% milk

1 tsp

kosher salt

1/2 tsp

black pepper

1/8 tsp

ground nutmeg

7 oz

2% Greek yogurt