In this cheesy chicken casserole, leftover mashed potatoes form the base, rather than the topping, as they do in shepherd's pie. Poaching bone-in chicken breasts in stock yields tender, juicy meat—use this method for enchiladas and chicken salad. Instead of draining and discarding the stock after poaching, return the liquid to the pan, and bring to a boil. Reduce heat and simmer until reduced to about 3 cups for a rich sauce or soup base. We love the texture and concentrated flavor of dried minced onion as the casserole topper, but you could skip it or substitute toasted, coarsely ground breadcrumbs.
How to Make It
Preheat oven to 400°F.
Bring stock to a boil in a large saucepan over high. Add chicken; reduce heat and simmer 15 minutes or until chicken is done. Drain. Remove skin and bones from chicken; discard. When chicken is cool enough to handle, shred into pieces.
Cook broccoli according to package directions. Combine chicken, broccoli, and next 5 ingredients (through pepper) in a large bowl. Stir in eggs and 2 ounces cheese (about 1/2 cup). Spoon mixture into a 9-inch square glass or ceramic baking dish coated with cooking spray. Bake for 15 minutes. Top with remaining 3 ounces cheese (about 3/4 cup). Bake for 10 minutes or until casserole is bubbly and cheese is melted.