Welsh Lamb chop hotpot

Ingredients

• 6-8 PGI Welsh Lamb chops
• 2 tbsp olive oil
• 2 carrots, peeled and sliced
• 1 leek, trimmed and roughly chopped
• 1 large onion, roughly chopped
• 2 tbsp plain flour
• 1l lamb stock
• 1 tbsp Worcestershire sauce
• Sprigs fresh rosemary and thyme
• 100g salted butter, melted
• 3 large floury potatoes, peeled and cut into 1cm rounds
• Salt and ground black pepper