In a saucepan, combine raspberries, orange juice & sugar. Cook, stirring, for 3-4 minutes or until sugar dissolves & raspberries have released their juices. Remove from heat.
Strain through a fine sieve into a medium bowl & using the back of a wooden spoon, push excess pulp through sieve. Return juice to the saucepan.
Combine cornstarch with water & add it to raspberry mixture. Bring to a boil, allowing puree to thicken to a custard consistency. Remove from heat & allow to cool.
Preheat oven to 375 F. Place an oven tray in the oven to preheat. Brush 4 ramekins with melted butter & dust with sugar. Set aside.
Raspberry Soufflé
Using an electric mixer, whisk egg whites in a medium bowl until soft peaks form adding 1 tablespoon of sugar while mixing to get a glossy texture. Gently fold the beaten egg whites into the raspberry mixture, starting with half of the quantity.
Once the egg whites have been fully incorporated into the raspberry mixture, pour evenly among prepared ramekins & fill them. Run your spatula around the top of each ramekin just above the soufflé mixture to remove the extras & clean the ramekins.
Place soufflés on the preheated hot tray & bake for 15-17 minutes or until puffed & cooked through. Remove from oven & place on serving plates. Dust with powdered sugar & serve immediately.