Baked Cheesy Potatoes

Name: Baked Cheesy Potatoes
Ingredients: 3 tablespoons extra-virgin olive oil; 1 medium onion, chopped; ¼ cup all-purpose flour; 2 cups low-sodium no-chicken broth or chicken broth; 1 cup reduced-fat milk; ½ teaspoon salt; ½ teaspoon ground pepper; 1 ½ cups shredded extra-sharp Cheddar cheese; 1 cup sour cream; ¼ cup grated Parmesan cheese; 1 (30 ounce) package frozen shredded hash browns, thawed; 1 cup crushed potato chips (2 ounces)