With a very sharp knife, cut both ends off the butternut squash. Place up right and slice off the outer skin.
With the squash still standing, cut the squash in half lengthwise. Scoop out the seeds with a spoon and discard. Cut the squash in 1 to 2 inch cubes.
Peel and core the apples.
Slice the apples in quarter inch thick slices.
Place the apples and squash in a large bowl and add the cinnamon, nutmeg, and brown sugar. Mix to evenly coat everything with the sugar and spices.
Place the apples and squash mixture in your crock-pot, slow cooker whatever you want to call it, and add 1/4 cup of water. Cover and cook on high for 4 to 5 hours or on low for 8 hours. At least once towards the end of cooking mash the squash and apples with a wooden spoon or potato masher. After it has finished cooking mash the squash and apples until you reach your desired texture.
Serve warm or cold. Store in the refrigerator in an air-tight container for 3 days or in the freezer for up to 3 months. For easy storage, freeze in a ice-cube tray and store in a freezer container or freezer bag.
* Please note that apples and butternut squash are perfect stage 1 baby foods (6 to 8 months), but spices should to be introduced after baby is 8 months old. And some babies (Mia was one of them) have a temporary sensitivity to cinnamon in their first year. Be cautious if you have never given your baby spices before.
—Recipe by Meredith Steele, In Sock Monkey Slippers