Place the egg whites in a medium bowl and using a handheld electric mixer, whip the whites on high speed for about 30 seconds, until foamy.

Add the cream of tartar and continue whipping as the egg whites thicken.

Once the whites reach soft peaks, start adding the sugar, one tablespoon at a time, and then beat to stiff, glossy peaks.

Pipe the mushroom stems: hold the piping tip perpendicular to the prepared baking sheet, squeeze a ¾-inch (2 cm) mound onto the parchment paper, then lift straight up and release the pressure to create a long Hershey kiss like shape. Repeat to make 25 stems.

Pipe the mushroom caps: hold the piping tip perpendicular to the prepared baking sheet, squeeze a 1½ inch (4 cm) mound, then release the pressure on the bag but instead of lifting the tip upward (which will create a peak) detach the tip by making a small circular motion. Repeat to make 25 caps. If you get any peaks, you can gently smooth them out with a slightly damp finger.

If you have more egg whites, continue piping an equal amount of stems and caps, piping everything about 1-inch (2½ cm) apart on both sheets.

Bake for about 90 minutes, rotating the pans halfway though, until the meringues are dry to the touch and release easily from the parchment. Let cool completely on the baking sheets.

When ready to assemble, use a thin pointed knife to poke a small hole in the bottom center of each mushroom cap.

With a small spoon, fill a few drops of melted chocolate into the hole and insert the tip of a stem.

Keep the mushrooms on its side for about an hour, or until the chocolate sets.

Store the mushrooms in an airtight container at room temperature for up to three days. Just before serving, sift a touch of cocoa powder on the caps.