Cook rice following the absorption method on the packet. Rinse under cold water. Drain well.
Heat 1 tbs oil in a large non-stick frying pan over medium heat. Add onion and cook, stirring occasionally, for 5 minutes until soft. Add the lemon rind and 2 tbs lemon juice and cook for 1 minute. Remove from heat, stir in rice, pine nuts, currants, parsley and season with salt and pepper.
Preheat oven and roasting pan to 220°C fan forced. Remove stalk from the mushrooms. Pile the pilaf onto the mushrooms. Place mushrooms into hot roasting pan and roast for 10 minutes until just tender. Season with salt and pepper.
Scatter over the rocket. Combine the remaining oil and lemon juice and spoon over the mushrooms. Serve.