Yes! Pop the cooled soup into freezer-friendly bags or containers. I recommend doing so in serving-size portions. Freeze it for up to 3 months. Transfer it to the fridge a day before serving. Reheat as usual and enjoy.
Add the butter and sliced onions. Cook until they’re slightly browned (not burned).
Add the garlic, thyme, mustard, and Worcestershire to the onions.
Pour in the wine and mix well. Stir to remove any browned bits and let simmer
Preheat the oven using the broiler setting. Scoop the soup into oven-safe bowls. Place on a baking sheet.
Place 1-2 slices of bread and 1-2 slices of cheese in each bowl.
Place the baking sheet in the oven. Broil the soup bowls for 2-4 minutes or until the cheese is melty. Remove the tray from the oven and serve immediately.