Big Batch Cheeseburger Bake

Big Batch Cheeseburger Bake
Original recipe here
I know the picture is awful but this stuff is SOO good, hubby and I both LOVE it :D

1 1/2 lb (at least 80%) ground beef
1 1/4 cups chopped onions (about 2 large)
1 can (10 3/4 oz) condensed Cheddar cheese soup
1 1/4 cups Green Giant® Valley Fresh Steamers™ frozen mixed vegetables (I used one can of drained green beans)
1/2 cup milk
2 1/3 cups Original Bisquick® mix
2/3 cup water
1 1/3 cups shredded Cheddar cheese (about 5 oz)
1. Heat oven to 375°F. Generously spray bottom and sides of 15x10x1-inch pan with cooking spray. In 12-inch skillet, cook beef and onions over medium heat, stirring occasionally, until beef is thoroughly cooked; drain. Stir in soup, vegetables and milk.
2. In large bowl, stir Bisquick mix and water until moistened. Spread evenly in pan. Spread beef mixture over batter. Sprinkle with cheese.
3. Bake uncovered 35 minutes.
High Altitude (3500-6500 ft): Do not add cheese before baking. Bake 35 minutes. Sprinkle with cheese; bake about 5 minutes longer or until cheese is melted.