Preparation Steps

• Position a rack in the center of the oven and preheat to 375°F. Lightly butter or spray a 9×13-inch baking dish.
• Spread the frozen hash browns on a sheet pan to take the chill off while the oven heats (5–10 minutes). Break up any clumps with your hands.
• Melt the butter in a skillet over medium heat. Add the diced onion and a pinch of salt; cook, stirring, until translucent and just tender, 4–5 minutes. Remove from heat and let cool 2 minutes.
• In a large bowl, whisk together the cream of chicken soup, sour cream, garlic powder, smoked paprika, kosher salt, and black pepper until smooth. Stir in the warm onions and 1 1/2 cups of the cheddar until the cheese just begins to melt into the sauce.
• Fold the hash browns into the sauce until every shred is coated. Scrape the mixture into the prepared baking dish and level the top. Cover tightly with foil.
• Bake covered for 20 minutes. Remove the foil, stir the casserole once to redistribute heat and creaminess, smooth the surface, and sprinkle the remaining 3/4 cup cheddar evenly over the top.
• Return to the oven and bake uncovered until bubbling at the edges and lightly golden, 18–22 minutes. For extra color, broil for 1–2 minutes, watching closely.
• Rest 10 minutes so it sets for clean scoops. Finish with chives and serve hot.