Cheese and onion puff pies | British Onions

Ingredients

• 3 Medium white onions
• 2 Tablespoons olive oil
• 2 Tablespoons fresh chopped rosemary leaves
• 450g/1lb Potatoes, peeled, thinly sliced
• 200g/7oz Full fat crème fraiche
• 100g/4oz Gruyere or mature cheddar cheese, grated
• 1 clove garlic, finely chopped
• Salt and freshly ground black pepper
• 500g/1lb 2oz Puff pastry, defrosted if frozen
• Little flour for dusting
• 6 Slices wafer thin honey roast ham
• 1 Egg, beaten