Preheat your oven to 400 degrees. Cook your bacon, either in a skillet or in the oven. When the bacon is done cooking, drain it on paper towels. Dab another paper towel in the drippings and grease 4 ramekins with the bacon drippings. Reserve 1 tablespoon of the drippings and either save the rest for later or discard them.

In a skillet (the same one you cooked the bacon in if you used a skillet), heat the reserved drippings over medium heat, then add the spinach. While the spinach is wilting, whisk together the vinegar and mustard. Stir the spinach frequently until wilted, then remove from heat and add the vinegar/mustard mixture. Season to taste with salt and pepper.

Carefully crack an egg into each ramekin. Divide the spinach evenly among the ramekins, then crumble the bacon and add that. Place the ramekins on a baking sheet and bake for 10-15 minutes or until the whites are just cooked through and the yolks are still runny (We baked ours for 13 minutes and they were a tiny bit overdone, so keep a close eye on them). Remove from the oven, season with salt and pepper, and divide the goat cheese evenly among the ramekins. Serve immediately with slices of toasted baguette.