About halfway through cooking the squash, start preparing the bacon.  In a large skillet over medium heat add the bacon slices. Stirring frequently, cook the bacon over medium heat until the edges just start to turn brown, approximately 2 minutes.  Turn heat to low and continue to cook for an additional 3 minutes.

When the bacon is done cooking, turn up the heat to high and add the apple cider vinegar to the pan while scraping the bottom with a spatula to remove any brown bits stuck to the bottom. Turn heat back down to low medium-low and add the chopped onion along with a dash of salt, pepper and red pepper flakes. Stir it all together and allow it to saute until onions turn soft and translucent, stirring occasionally. Add in the minced garlic and stir again.  Allow the garlic and onions to saute for an additional minute or two and then add the spinach to the skillet, one handful at a time (it shrinks to nothing). Stir after each addition, making room for more for more spinach.

When spinach is finished cooking, turn off heat and set aside.  Meanwhile, check on the squash.  As soon as the squash is fully cooked, remove from the oven.  Use a fork to peel flesh away from the skin (this should be easy).  Add to the skillet with the bacon and spinach and gently mix everything together.

Serve immediately with a generous amount of goat cheese or other favorite cheese.