Cut the peaches into quarters and discard the pits. Brush the cut side of the peaches with canola oil.
Place the peaches on the preheated grill on one of its flat sides that has just been cut (cut side down. Close the lid and grill for 2–3 minutes, or until grill marks appear.
Flip the peaches to the other flat side (also cut side down) and grill for 1–2 more minutes, or until grill marks appear and the peaches have softened just slightly.
Place the heavy cream in the bowl of a stand mixer. Mix on high until soft peaks form. Add the honey and vanilla extract, and beat just until combined.
Place the grilled peaches on a serving platter. Top each peach quarter with a dollop of whipped cream and a sprinkle of chopped pistachios. Garnish with fresh mint, if desired.
Notes
Make sure that your peaches are just beginning to ripen, and are not too soft. If they are too soft, they will fall apart on the grill.Nectarines or apricots would be delicious instead of peaches!Clean the grill with a grill brush or with a wad of aluminum foil before grilling the peaches.