• 500 g potatoes, sliced wafer thin
• 1 large parsnip, sliced wafer thin
• 1 large beetroot, sliced wafer thin
• 1 large sweet potato, sliced wafer thin
• 3 cloves of garlic, thinly sliced
• Pinch of salt
• 1 tbsp chopped fresh rosemary
• 275 ml double cream
• 150 ml full-fat milk
• 60 g Parmesan, grated

Preheat the oven to 180°c and butter a shallow ovenproof dish. Layer some of the potatoes, then parsnip, beetroot, and sweet potato in the dish. At the halfway point, scatter over two of the sliced garlic cloves, a little salt and half the rosemary. Keep making layers until you have used all the vegetables.

Pour the cream and milk into a saucepan then add the rest of the rosemary and garlic, half the Parmesan and a little seasoning. Gently heat for 3 minutes.

Pour the cream mixture over the layered vegetables. Sprinkle over the remaining Parmesan, cover the whole dish with foil and bake for 40 minutes. Remove the foil and bake for a further 15 minutes until golden and bubbly.

If you don’t like Parmesan, just replace it with a good quality cheddar, or if you want the gratin to be extra cheesy, sprinkle cheddar on top in addition to the Parmesan.