CREMINI MERINGUE MUSHROOMS

Steps:

• Heat oven to 200°F with racks in upper and lower thirds. Line 2 large baking sheets with parchment paper.
• Beat egg whites with cream of tartar and salt in bowl of stand mixer on high speed until they just hold soft peaks. Beat in sugar, 2 tablespoons at a time, beating well after each addition, and continue to beat at high speed until meringue is very stiff, about 2 minutes. Beat in vanilla and beat again until very stiff.
• Sift cocoa over meringue, and fold it in gently but thoroughly.
• Spoon meringue into a pastry bag fitted with tip. Holding bag vertically, about 1/2 inch above baking sheet, pipe meringue into 25 mounds, ranging in size from about 1 1/2 to 2 inches in diameter, to resemble mushroom caps.
• Still holding pastry bag vertically, pipe remaining meringue vertically into 25 "stems," 1 1/4- to 1 1/2 -inch-long lengths (make different lengths), making each base about 1 inch in diameter and tapering top end by pulling up on bag. (Pipe extra caps and stems with any remaining meringue in case of breakage.)
• With a finger dipped in water, gently tamp down any peaks of meringue on caps to make a smooth mushroom cap.
• Bake, switching position of sheets halfway through, until mushrooms caps are crisp and firm to touch, about 1 hour 45 minutes.
• Turn off oven, then leave meringues in oven, with door closed, 30 minutes to dry. Slide parchment with meringues from baking sheets onto racks to cool. Cool completely.
• With tip of a sharp paring knife, cut a small hollow the diameter of the tapered top of mushroom "stem" in center of the underside (flat side) of each mushroom cap.
• Spread chocolate generously over flat bottom of a cap with offset spatula or back of spoon, then insert narrow end of stem. Let cap rest, stem end up, on a tray or baking sheet. Attach remaining stems to remaining caps, and let stand, stem ends up, at cool room temperature until chocolate is set, about 1 hour.