Gather all ingredients.

Preheat the oven to 225 degrees F (110 degrees C). Line 2 cookie sheets with parchment paper or aluminum foil.

Beat egg whites in a large glass or metal bowl with an electric mixer until foamy. Add vanilla, cream of tartar, and salt.

Continue whipping until soft peaks form. Gradually sprinkle in sugar so that it does not sink to the bottom and continue whipping until meringue holds stiff shiny peaks. Place a round tip into a pastry bag and fill the bag halfway with meringue.

To pipe mushroom caps, squeeze out round mounds of meringue onto one of the prepared cookie sheets. Pull the bag off to the side to avoid making peaks on the top. Refill the bag with meringue as needed.

To pipe mushroom stems, press out a tiny bit of meringue onto the remaining cookie sheet, then pull the bag straight up. They should resemble candy kisses. Do not worry about making all of the pieces exactly the same. The mushrooms will look more natural if the pieces are different sizes.

Dust mushroom caps lightly with cocoa using a small sifter or strainer.

Bake in the preheated oven until meringues are dry enough to easily remove from the cookie sheets, about 1 hour. Set aside to cool completely.

Melt coating chocolate in a metal bowl over simmering water or in a glass bowl in the microwave, stirring occasionally until smooth.

Rotate the tip of a paring knife in the bottom of a mushroom cap to create a small hole. Spread chocolate over the bottom of the cap. Dip the tip of a stem in chocolate and press lightly into the hole.

When chocolate sets, the cap and stem will hold together. Repeat with remaining meringues. Store at room temperature in a dry place or tin.