Lightly grease soufflé dishes with butter and sprinkle with sugar before placing the ramekins in the freezer.
For the coulis, add half of the sugar to the raspberries and place in a hot sauceplan to simmer for 2-3 minutes with a good squeeze of lemon juice. Blend using a hand blender and sieve to remove seeds. Pour 2 tsp of coulis in the bottom of the ramekins and thicken the remaining coulis with the moistened cornflour.
For the merringue, ensure the whisk and bowl are completely clean. Place the egg whites in the bowl and whisk.
Slowly add sugar while whisking until a smooth soft peak is reached.
Add a dash of lemon juice at the end.
For the soufflé, use a third of the meringue and whisk it into the thickened coulis.
Lightly fold in the rest of the merringue.
Divide the mixture evenly between the dishes.
Transfer to a medium to hot oven (180°C/350°F/Gas 4) for approximately 10-15 minutes.
Sprinkle with icing sugar and serve immediately with fresh raspberries.