Spoon the oil and red curry paste into a large cold wok. Place over medium heat and cook, stirring, for 4-5 minutes or until aromatic. Add the thick top layer from the top of the can of coconut cream, cook for 1-2 minutes or until it splits (this is known as cracking the milk. Add the remaining coconut cream and stock. Bring to the boil. Reduce heat to low and boil gently for 3 minutes or until reduced slightly.
Add the duck and pak choy stems, simmer for 4-5 minutes until the duck is warmed through.
Cut some of the grapes in half. Add all the grapes to the curry. Stir in the fish sauce and pak choy leaves. Remove from the heat. Squeeze over the lime, top with basil leaves and shallots. Serve with rice.
TipTip: Cooked Peking duck breast is available from most supermarkets Alternately, cooked whole barbecue duck can be purchased from some Asian grocery stores or you can use cooked chicken.
TipTip: When you shred the leaves and stems of the pak choy, keep them separate as the stems require a little longer cooking than the leaves. Be sure to rinse the stem well, to remove any dirt.