Turkey tail (Trametes versicolor) is one of the most studied medicinal mushrooms with some well documented, potent action, particularly for treating cancer... and if not spotted growing on some deadwood in your garden (or like us, on your un-chopped log pile!), no doubt it can be found proliferating away in your local park or greenspace.
Always harvest lightly, taking only what you need (which might not be achieved if there is only one cluster). Pick those of a vibrant nature, that are white underneath and not greenish-brown. 'Crust' fungi can look a bit similar but do not have wee holes (pores on the underside), and don't always have a white outermost band (margin).
You can add honey to taste for this recipe too should it be too earthy for you!