Cheesy gnocchi French onion soup | Women's Weekly Food

Ingredients

• 50 grams unsalted butter, chopped
• 1 tbsp extra virgin olive oil, plus extra for drizzling
• 1 kg brown onions, sliced thinly
• 2 cloves garlic, crushed
• 1 tbsp brown sugar
• 1 tbsp Dijon mustard
• 2 tbsps balsamic vinegar
• 4 sprigs thyme, plus extra to serve
• 2 tbsps plain flour
• 1 l beef stock
• 250 grams store bought potato gnocchi
• 1 cup (120g) coarsely grated gruyere cheese
• ¼ cup (30g) coarsely grated mozzarella cheese