Ingredients
Instructions
- Melt butter in a large saucepan over medium heat. Add onions and sea salt and cook, stirring occasionally, for 30 minutes or until onions are deep golden.
- Add cider and simmer until reduced by half, then add stock and simmer for 10 minutes. Season with pepper.
- Meanwhile, place bread on a foil-lined tray and cook both sides under a hot grill until dried but not browned. Spread with mustard and top with cheese, then grill until cheese bubbles and browns.
- Serve soup topped with the croûtons and sprigs of thyme.