Preheat the oven 350F. Brush butter in 8 small ramekins and dust with sugar (may use more or less ramekins depending on their size). Place ramekins on a baking sheet.
Place raspberries in a medium sauce pan over medium heat. Bring to a low boil for 3 minutes. Take off heat and purée in a food processor or blender. Strain through a fine sieve and place back in sauce pan over medium heat. Add lemon juice and sugar and stir until dissolved. Place water and cornstarch in a small bowl and whisk together. Bring raspberry mix to a boil and whisk in cornstarch mixture, continue to mix for 1 minute. Remove from heat and allow to come to a compete cool in the refrigerator.
Place egg whites in a stand mixer and beat until soft peaks form. Slowly add sugar. Beat until it begins to look glossy. With a spatula gently fold in the raspberry mixture.
Spoon the mixture into each ramekin. Even out the tops with a knife. Bake in the oven for 12 to 15 minutes, or until soufflés have risen. Dust with powdered sugar and serve immediately.
Recipe by pretty plain janes at https://prettyplainjanes.com/2016/02/10/raspberry-souffle/