01 -
Preheat oven to exactly 350°F and thoroughly coat 9x13 baking dish with cooking spray.
02 -
Combine thawed green beans, cheddar soup, milk, minced onion and all seasonings in large mixing bowl.
03 -
Add shredded cheddar and parmesan cheeses to green bean mixture, stirring until evenly distributed.
04 -
Transfer seasoned green bean mixture to prepared baking dish, spreading into even layer.
05 -
Set aside Cheddar Bay seasoning packet and combine dry biscuit mix with shredded cheese in bowl.
06 -
Add milk to biscuit mixture and stir gently until just combined with no large lumps remaining.
07 -
Pour prepared biscuit batter evenly over green bean layer in baking dish.
08 -
Bake uncovered for 50-55 minutes until biscuit topping becomes golden brown.
09 -
Mix reserved seasoning packet with melted butter while casserole bakes.
10 -
Remove casserole from oven and immediately brush with seasoned butter mixture.
11 -
Allow casserole to rest 5 minutes before serving to absorb butter topping.