Tomato and Gruyère Tart Recipe - Great British Chefs

Ingredients

• 250g of plain flour
• 125g of butter, chilled and diced
• 1 pinch of salt
• 50g of Gruyère, finely grated
• iced water, 1–2 tbsp
• 120g of butter
• 1kg large onions, peeled, halved and sliced
• 4 garlic cloves, peeled and chopped
• 1 tbsp of chopped rosemary
• 100g of Gruyère, finely grated
• 500g of ripe tomatoes, sliced
• olive oil, to drizzle
• salt
• pepper