If you have a butternut squash left over from your market haul and are not sure what do with it, look no further This butternut squash casserole is a simple combination of mashed butternut squash with eggs, maple syrup, and spices. Then the mashed butternut squash is baked with a crunchy brown sugar and pecan topping. This recipe is super easy to assemble and doesn't require much time. Consider making it for your next holiday dinner or an everyday meal. It's also a nice balance of sweet and savory, that it could even work for an autumnal brunch. When paired with some pork and maple sausages or a harvest veggie frittata, this casserole would fit right in. If you want to, this casserole can be prepared ahead of time (even the night before if you are making it for brunch). Make and prepare the casserole filling and topping, but do not place the topping on the casserole. Once you are ready to bake it, add the topping and proceed with the recipe. Be sure to use real maple syrup. It has a much better flavor than any syrup substitute. Store any leftover casserole in a sealed container in the refrigerator for 4 to 5 days. To reheat it, either scoop individual portions onto a microwave-safe plate and heat or place the room temperature casserole into a warm oven. You may want to cover it with foil while it warms to prevent the top from becoming too brown. If you had the casserole for dinner, consider eating leftovers for breakfast. Add some scrambled eggs or top the casserole with a fried egg.