Pour the onions into your slow cooker.
Drizzle in butter, olive oil, and season with salt and pepper.
Set to low and let it work its magic for 10-12 hours till the onions are golden.
Stir in the beef stock, balsamic vinegar, and thyme leaves.
Cook covered on low for another 6-8 hours. Season as needed, and feel free to add the brandy.
Get your oven ready at 350°F (180°C).
Spoon the soup into oven-proof bowls and place them on a baking sheet.
Crown each bowl with toasted bread and a sprinkle of Gruyere cheese.
Bake for 20-30 minutes till cheese melts. For an extra golden touch, broil for 2-3 minutes.
Once cooled a tad, dive into your comforting bowl of French Onion Soup! The beautiful union of caramelized onions, aromatic broth, and rich cheese guarantees a meal that hugs your soul and pleases your palate. Enjoy!
Credit: Home Remedies Easy