Chard, Potato and Gruyère Gratin

Ingredients

• 500 g Swiss chard, stems and leaves separated, both roughly chopped
• 900 g waxy potatoes, peeled and sliced 3mm thickCharlotte or Desiree work well
• 150 Gruyère, coarsely gratedComté or mature Cheddar also work
• 300 ml double cream
• 150 ml whole milk
• 3 cloves garlic, finely grated
• 20 g unsalted butter
• 2 egg yolks
• ¼ tsp freshly grated nutmeg
• 1½ tsp fine sea salt
• ½ tsp black pepper, freshly ground

Contains: eggs, milk.

Method

1. Preheat the oven to 180°C fan. Rub a 30cm x 20cm baking dish with the butter.
2. Heat a large, dry frying pan over a medium-high heat. Add the chard stems and cook for 3 minutes until they begin to soften. Add the chard leaves and cook for a further 2 minutes, stirring, until wilted and any liquid has evaporated. Season with a pinch of salt, then set aside.About 5 min
3. Whisk together the double cream, milk, grated garlic, egg yolks, nutmeg, 1 tsp salt and the black pepper in a jug until combined.About 2 min
4. Arrange half the potato slices in overlapping layers in the buttered dish. Season lightly. Spread the wilted chard evenly over the potatoes, then scatter over half the Gruyère. Layer the remaining potatoes on top, overlapping neatly.About 8 min
5. Pour the cream mixture slowly and evenly over the gratin so it seeps down through all the layers. Press the top layer of potatoes down gently with your hands.
6. Scatter the remaining Gruyère over the top. Cover tightly with foil and bake for 40 minutes.About 40 min
7. Remove the foil and bake for a further 15 minutes until the top is deep golden and the potatoes are completely tender when pierced with a knife. Leave to rest for 5 minutes before serving.About 15 min