Barney's Broccoli Casserole

2 pkgs frozen chopped broccoli
1 cup shredded cheddar cheese
1/2 cup mayonnaise (real mayonnaise, not Miracle Whip)
1 can cream of mushroom soup
1-1/2 teaspoons onion powder
1 small can of mushrooms
1 egg
dash of salt and pepper
Cook broccoli according to directions and drain.
Mix together all ingredients, add cooked broccoli
In a buttered 2 quart bowl, bake at 350 degrees for 45 minutes