Stone and finely slice the peaches or nectarines and arrange the slices over four plates. Sprinkle over a little of the sugar and scatter over most of the thyme leaves.

Whisk together the mascarpone, cream, vanilla extract and the remaining sugar in a bowl until light and fluffy. Spoon or pipe blobs of the mixture over the peaches or nectarines and arrange the raspberries over the plates. Finish with a scattering of pistachios, the remaining thyme leaves and a drizzle of maple syrup to serve.