Preheat the stove to 180°C (gas mark 4).
Butter a glass or porcelain casserole about one and a half liters (when preparing for 4 people) evenly and accurately, dust with powdered sugar.
Beat the egg yolks with half of the powdered sugar and two thirds of the passion fruit juice.
Whip the egg whites with the remaining powdered sugar until very creamy. Fold the mixture very gently into the egg yolk mixture. Pour the mixture into the prepared vessel, smoothing the surface.
Meanwhile, bake in the heated oven for twenty-five to thirty minutes.
For the sauce, bring the remaining passion fruit juice to a boil with the sugar, lime juice and a small amount of water. Thicken with the cornflour. Stir well.
To serve: When the souffle is ready, dust sugar on top and bring to the table on the spot. Add the lukewarm sauce separately, possibly with a little whipped cream or yogurt.