Prep
Line two baking sheets with parchment paper or silicone mats.
Fit a piping bag with a round tip.
Sift almond flour, powdered sugar, and cocoa powder together twice to remove lumps.
Make the Meringue
In a clean bowl, beat egg whites on medium speed until foamy.
Add cream of tartar (if using).
Slowly add granulated sugar while mixing.
Increase speed to medium-high and beat until stiff, glossy peaks form.
Beat in vanilla extract.
Macaronage (Folding)
Gently fold dry ingredients into the meringue in batches using a spatula.
Continue folding until batter flows like thick lava and ribbons disappear into the batter within ~10 seconds.
Pipe & Rest
Pipe 1½-inch circles onto prepared baking sheets.
Tap trays firmly on the counter to release air bubbles.
Rest macarons at room temperature 30–45 minutes, until tops are dry to the touch.
Bake
Bake at 300°F (150°C) for 15–18 minutes, rotating trays halfway.
Cool completely before removing shells from the pan.
Assemble
Pair shells by size and fill with your chosen filling.
Gently sandwich together.