Step 1: Preheat a fan forced oven to 220C

Step 2: Place the walnuts on a baking tray in the preheated oven for five minutes. Remove them from the oven and place on a tea towel. Gently rub to remove the skins. Set aside.

Step 3: In a medium size bowl mix the butter, finely chopped garlic, finely chopped flat leaf parsley, lemon zest, Extra Virgin Olive Oil and roughly chopped walnuts together. Wrap the walnut butter in cling wrap into a thick log shape and put in the fridge for an hour to set in shape.

Step 4: Lay the mushrooms on a baking tray and season with salt and some freshly cracked pepper.

Step 5: Slice the butter into eight roughly equal discs and place one disc on top of each mushroom with some fresh thyme sprigs and lemon zest and drizzle them with Extra Virgin Olive Oil. Place in the preheated oven and cook for five minutes. 

Step 6: Remove and drizzle over the Verjuice. Return to the oven and cook for another two to three minutes.

Step 7: Remove from the oven and serve with fresh thyme flowers (optional) and a drizzle of Extra Virgin Olive Oil.