Spray a 13-inch by 9-inch by 2-inch baking dish with cooking oil spray (or grease with butter or oil). Arrange Tater Tots in evenly in the bottom of the prepared baking dish. In a large mixing bowl, combine 16 oz. sour cream, 1 cup shredded Cheddar cheese, a 10.75 oz. can cream of mushroom soup, and ? cup sliced green onions. Stir until well blended. Pour mixture over the Tater Tots. Bake at 350 degrees for 45 minutes. Sprinkle a can of potato sticks over the top of the casserole, and cook for an additional 5 minutes. Remove from the oven, and serve while hot! This casserole is a favorite around here. It is very simple to make, and goes with just about anything. It is very tasty!