Try switching the broccoli with cauliflower or thawed and grained mixed frozen veggies.No one ever says no to biscuits! My Bisquick biscuits are a snap to make and would be a delicious addition! Variations + Substitutes, + Additions If you want to add a side dish, a simple green salad works nicely, dressed with my balsamic vinaigrette recipe (one of my all-time favorite dressings and it only takes 5 minutes to put together!), or add another vegetable even the kids will love my super easy brown sugar carrots. One thing I love about this casserole is it’s a complete meal all on its own. Place leftovers in a small baking dish and cover with foil. Reheat Leftover: Preheat oven to 350☏.On dinner night, add your cheesy breadcrumb topping and toss it in the oven. Combine your ingredients and spread them into a prepared baking dish.Make-Ahead Tips: This chicken broccoli casserole is fantastic for meal prep! You can make it ahead of time the same way you prepare to freeze it.When you’re ready to pop it in the oven for dinner, that’s when you mix up your savory crunchy topping and cover your casserole. Wrap it up and toss it in the freezer instead of the oven.If you know you’re going to be freezing this, then prepare as directed without the cheesy breadcrumb topping. I often make two casseroles and put one in the freezer for later. Can You Freeze This? Yes, and I do this myself.How Long Can You Keep This In The Fridge? This can stay in the fridge for up to 3-4 days.So, you definitely want to preheat your oven before baking this to achieve the best results. If food is already in the oven, this quick blast of heat can char the outside while leaving the inside raw. Preheating Oven– Ovens preheat differently and some are designed to use both a top and bottom element to preheat quickly.Baking Dish – Use a 9×13 baking dish and spray it with nonstick cooking spray.