1cup(226 g or 2 sticks) unsalted butter, room temperature
2 ½cups(300 g) confectioners' sugar, sifted
Eggnog additions
1Tablespooneggnog
½teaspoonground nutmeg
¼teaspoonrum extract
Peppermint additions
1Tablespoonmilk
¼teaspoonpeppermint extract
Crushed peppermint candies for decoration
Gingerbread additions
1-2teaspoonsmilk
1Tablespoonmolasses
½teaspoonground ginger
¼teaspooncinnamon
¼teaspoonground allspice
Instructions
Macarons
Place egg whites in a small bowl (make sure there is no trace of egg yolk). Cover with plastic wrap and poke a few large holes in it. Leave out at room temperature for 8 hours or in the refrigerator overnight. Bring to room temperature before using.
Place confectioners' sugar and fine almond flour into a fine mesh sieve over a bowl. Sift and let the bowl catch the sifted ingredients. Discard any large clumps in the sieve. Repeat twice more and set aside dry ingredients.
Put egg whites in a very clean bowl of a stand mixer fitted with a whisk attachment. Whisk eggs on medium-low speed for a minute or two until frothy then add the cream of tartar and salt. With the mixer running, very slowly add the bakers sugar (either 2 teaspoons at a time or in a very slow sprinkle into the bowl). Increase speed to medium-high and beat until stiff peaks form, about 5 minutes on KitchenAid Stand Mixer speed 6. Pro tip: The mixture will ball up in the whisk and the mixture will stay in the bowl if turned upside down.
Remove mixing bowl from stand mixer. Add half of the almond flour mixture to the bowl. Use a silicone spatula to gently fold the dry ingredients into the wet ingredients. Once mostly incorporated, add the remaining dry ingredients. Continue folding by going around the sides of the bowl with the spatula, then cutting through the center. The batter is done when it has a lava-like consistency. Do not over-mix. Pro tip: Try lifting the spatula out of the bowl and forming figure 8 with the batter without it breaking.
Transfer batter to a piping bag fitted with a round tip (about 1/2-inch in diameter). Pipe batter onto a silpat mat with macaron outlines or onto parchment paper. Pipe circles 1-inch wide and spaced 2 inches apart. Lift the baking sheet about 6 inches off the counter and drop it down. Repeat twice more, then rotate the pan 180° and bang the pans three more times (this releases air bubbles from the macarons).
Let the macarons sit at room temperature for 40 to 45 minutes and up to an hour. The macarons are ready to bake when dry to the touch (you should be able to "pet" them without leaving a mark).
Ten minutes before macarons are done drying, preheat the oven to 300° F. Bake macarons for 12 to 14 minutes, rotating the pan halfway through. Cool completely.
Buttercream Frosting Fillings
In the bowl of a stand mixer, whip the butter on medium-high speed using the paddle attachment. Beat until fluffy, about 5 minutes.
With the mixer on low speed, gradually add in the confectioners' sugar until completely incorporated.
Divide the buttercream mixture equally into three bowls. To the first bowl, add the eggnog additions and mix until smooth. To the second bowl, add the peppermint additions and mix until smooth. To the third bowl, add the gingerbread additions and mix until smooth. If at any time the frosting is too thick, add 1 to 2 teaspoons of milk until desired consistency is reached.
Transfer frostings into three piping bags with desired tips. Match macaron cookies according to size. Frost the bottom of one macaron cookie and top it with a matching cookie. Press down gently. If making peppermint macarons, roll the sides of the cookie sandwich in crushed peppermint. For eggnog macarons, add a dusting of nutmeg to the cookie shell to differentiate them.
Notes
Bakers sugar is a superfine granulated sugar. If you can't find bakers sugar, use granulated sugar and process it in a food processor for ten 1-second pulses.Fillings: If you only want one flavored filling, keep the buttercream base as is and add triple the flavored additions.Dye your macarons: Add 1 to 2 drops of gel food coloring during the last minute of whipping your egg whites.Store in the refrigerator for 2 weeks. Bring to room temperature before serving. Freeze macarons (assembled or unassembled) in an airtight container for up to 3 months. Place parchment paper between layers so cookies do not stick. Defrost overnight in the refrigerator before bringing to room temperature.