Using a large sieve, sift the almond flour and powdered sugar together into a large bowl. Then sift the mixture a second time into another large bowl. Set aside.
In a large bowl, pour in the egg whites and cream of tartar. Beat the egg whites on medium-low speed until soft peaks form.
Add the granulated sugar to the eggs. Continue beating until the mixture almost reaches stiff peaks.
Add the red gel food coloring and peppermint extract and beat until stiff peaks form, and you can tip the bowl upside down and nothing falls out.
Fold in a third of the dry ingredients to the egg white mixture with a spatula until completely mixed. Fold in the rest of the ingredients until the batter can run off the spatula forming a “figure-8” without breaking. Be careful not to overmix the batter or you will lose air bubbles from the egg whites.
Scoop the batter into a large piping bag fitted with a large round tip (I used a Wilton 2A tip). Pipe 1 to 1½ inch circles onto parchment-lined baking sheets, leaving about 1 to 2 inches between each macaron. You can also use a silicone macaron mat.
Tap the pan on the counter at least 5 times to release air bubbles to the top of the macarons. Use a toothpick to pop any bubbles on the surface.
Allow the macarons to rest in a dry area for 30 minutes to an hour until the tops of the macarons are no longer tacky to the touch.
Preheat the oven to 315°F/157°C.
Bake the macarons, one cookie sheet at a time, for 17 minutes. The cookies should rise and form “feet” as they bake.
Let the macarons cool on the pan set on top of a cooling rack for 10 minutes. Then remove the pan, keeping the macarons on the parchment paper, and leave on the cooling rack until completely cool, at least 10 more minutes. The macarons should peel off of the parchment paper leaving little to no cookie residue on the parchment paper.
In a large mixing bowl, cream the softened butter with a handheld mixer on medium speed. Gradually add the powdered sugar until it is well mixed with no lumps.
Add the cocoa powder, and mix until completely incorporated. Then add the peppermint extract and 1 tablespoon of heavy whipping cream. Mix well on medium speed. If the buttercream is still thick or clumpy, add in a second tablespoon of cream. Mix until the texture is smooth and creamy.
Add the buttercream to a piping bag and pipe the buttercream on the flat side of half of the macaron cookies. Then place the other half of the macarons on top of the buttercream to form a macaron sandwich.
Roll the macarons in the crushed candy canes to coat the edges.
