Parsnip and carrot gratin | Sainsbury`s Magazine

Ingredients

• 500g carrots, peeled
• 500g parsnips, peeled
• 3 tbsp olive oil
• 1 large onion, finely chopped
• 2 tsp chopped thyme leaves
• 3 bay leaves
• 1 x 300ml carton double cream
• 450ml whole milk
• 4 garlic cloves, crushed
• 2 tbsp Dijon mustard
• 50g Parmesan or vegetarian alternative, finely grated
• a grating of whole nutmeg, to taste
• 40g panko or other dried breadcrumbs
• 40g soft butter