1/2 cup unsweetened cocoa powder, preferably Dutch process
3 large egg whites
Preheat the oven to 400°. Line a large baking sheet with parchment paper. Using a large metal spatula, spread 1/2 cup of the batter across the parchment paper as thinly as possible. Draw a large, clean, long-toothed comb along the length of the batter to make spaghetti-like strips. Bake for 3 to 4 minutes, or until the batter is just cooked through but still pliable.
Working quickly and beginning at one end of the strip, use a metal spatula to remove 7 or 8 of the spaghetti "strands." Wrap the warm strands around a 3-inch ramekin or other round dish and let them cool and crisp up. You will need to make a total of 6 bands of chocolate spaghetti to garnish the soufflés. Gently remove the strands of spaghetti once they have hardened.
The bands of chocolate spaghetti can be stored at room temperature in an airtight tin for up to 2 days.