Shiitake & savoy upside down cake recipe

Ingredients

• 1 lb (450 g) waxy potatoes, unpeeled
• 1 large Savoy cabbage, leaves plucked off, hard central veins cut out and discarded
• ½ tsp cubeb peppercorns
• 2 tsp white peppercorns
• 1 tsp cumin seeds
• 1 oz (30 g) unsalted butter
• 2 tbsp olive oil
• 2 large onions, sliced
• 1 tsp Kashmiri chilli flakes
• 4 garlic cloves, finely chopped
• 6 oz (175 g) fresh shiitake mushrooms, halved
• 1 tsp sea salt
• 10 fl oz (300 ml) double cream
• 5 large egg yolks (use the egg whites to make meringues)
• Sunflower oil, for greasing
• Sea salt and freshly ground black pepper

1. In a saucepan, boil the potatoes in enough water to cover for 25 minutes or until soft. Then, holding the hot potatoes in a clean tea towel, peel them, then slice into rounds about 5 mm (¼ in) thick.
2. Put the cabbage leaves in a pan of boiling salted water and boil for 1 minute to blanch them. Drain and pop into a bowl of ice-cold water. Leave until completely cold. Drain and pat dry with kitchen paper.
3. Finely grind the cubebs, white peppercorns and cumin seeds using a mortar and pestle. Heat the butter and olive oil in a frying pan. Add the onions and cook gently until soft. Add the spices, chilli flakes, garlic, mushrooms and salt, stir and cook for 1 minute. Pour in the cream, turn up the heat and bring to the boil, then simmer rapidly for 5 minutes. Stir and pour the mixture into a heatproof bowl. Set aside to cool completely.
4. Preheat the oven to 180°C (gas mark 4). Stir the egg yolks into the mushroom mixture, one at a time, and season with salt and pepper to taste. Add the potatoes and gently fold to combine everything together.
5. Lightly oil a 1 kg (2 lb 4 oz) loaf tin and line its sides and base with the blanched cabbage leaves so that they overlap each other slightly and fall over the top. Reserve a couple of leaves to cover. Pour in the mushroom mixture and cover with the reserved leaves. Stand the tin in a roasting tin of hot water, cover with a sheet of moistened greaseproof paper and bake for 1 hour. Leave to cool in the tin for 10 minutes, then invert the tin onto a board. Cut the terrine into thick slices and serve immediately.