Peppercorn mushrooms with butter bean mash

Method

1. Put the porcini in a small bowl and cover with 150ml just-boiled water, then set aside to soak. They only need about 15 minutes but if you have time then a longer bath (up to 24 hours) will produce an even deeper flavour.
2. Drain half the liquid from the butterbeans then put the remaining liquid and beans themselves in a saucepan with the garlic. Put over a medium heat to warm through, stirring regularly. Once hot, use a stick blender to whizz until very smooth. Season well then cover to keep warm.
3. Put a heavy-bottomed frying pan over a high heat. Once it’s smoking hot add the oil, swirling to coat evenly. Add the mushrooms then sit another (clean) heavy pan on top and press down – the mushrooms should ferociously sizzle (it is quite loud!). Keep pressing for about 10 seconds, then remove the top pan and allow to cook for a few minutes, without stirring, until the liquid released from the mushrooms evaporates.
4. Season the mushrooms with salt and half of the crushed peppercorns. Flip the mushrooms, then cover and press again. Leave the pan sitting on the mushrooms for a few minutes while they cook, then remove and season again, using the remaining peppercorns. Transfer the mushrooms to a plate and cover to keep warm.
5. Return the pan to a medium-high heat and add the wine to deglaze. Once the wine has reduced by two thirds, add the porcini mushrooms and their soaking liquid to the pan. Bubble until thickened then stir in the oat fraiche and season with salt.
6. Divide the butterbean mash between plates, then top with the mushrooms and wilted spinach. Spoon over the porcini sauce.