French Onion Soup | Donna Hay

Ingredients

• 50g unsalted butter
• 1 tablespoon extra virgin olive oil
• 1kg onions, thinly sliced
• 4 cloves garlic, thinly sliced
• 1 tablespoon brown sugar
• 2 tablespoons plain (all-purpose) flour
• 6 sprigs thyme
• 1 litre beef stock
• 2 tablespoons balsamic vinegar
• 8 thin slices baguette
• 1 cup (125g) gruyere, grated
• 1 tablespoon thyme leaves
• cracked black pepper