- Preheat oven grill.
- In a saucepan, heat oil over medium-high heat. Add onions, apples and garlic. Cook for about 3 minutes, or until onions are translucent. Sprinkle with flour and stir well. Pour in cider and bring to a boil. Cook, uncovered, for 5 minutes, stirring occasionally.
- Add beef stock and the bay leaf. Season with salt and pepper. Reduce heat to low and simmer soup, covered, for 20 minutes. Pour into six ovenproof individual soup bowls. Place a slice of toasted bread on soup in each bowl. Top with grated cheese and green onions.
- Place soup bowls on a rimmed baking sheet. Broil under grill until cheese bubbles and is slightly browned. Serve immediately.
Aide-gourmet tip: Replace cider by red beer and goat's cheese by smoked Gouda.