Buffalo Chicken Tater Tot Casserole

Name: Buffalo Chicken Tater Tot Casserole
Ingredients: 1 (10.5-ounce) can cream of chicken soup (such as Campbell’s®); 3/4 cup ranch dressing; 2/3 cup sour cream; 1/2 cup buffalo-style hot sauce (such as Frank’s RedHot); 1/2 teaspoon garlic powder; 1/4 teaspoon black pepper; 5 cups shredded rotisserie chicken (from 1 [3-lb.] rotisserie chicken); 6 ounce sharp Cheddar cheese, shredded (about 1 1/2 cups), divided; 6 cups (28 ounce) frozen potato tots (from 1 [32-ounce] pkg.); Chopped scallions, for garnish