2 heads of broccoli, cut into florets (or 3 10.8-ounce bags of frozen broccoli florets)
2 eggs
1 large onion, diced (I used 1 cup of frozen diced onion as a shortcut)
1 (10.5 ounce) can condensed cream of mushroom soup (NOT diluted)
1/2 cup mayonnaise
2 cups (8 ounces) shredded cheddar cheese
1 (6 ounce) box stuffing mix (I used a 6-ounce box of Stove Top Chicken Flavored Stuffing)
4 tablespoons butter