Sift the almond flour, powdered sugar, and cocoa powder together twice into a medium bowl. Set aside.
In a heatproof bowl, combine egg whites and granulated sugar. Place over a pot of simmering water (double boiler). Whisk constantly for 2-3 minutes until sugar completely dissolves and mixture reaches 120°F. Test by rubbing a small amount between your fingers - it should feel smooth, not grainy.
Transfer the warm egg white mixture to your stand mixer bowl. Beat on medium-high speed until soft peaks form. Add vanilla extract and red gel food coloring. Continue beating on high speed until stiff, glossy peaks form and the bowl can be turned upside down without the meringue moving.
Add one-third of the sifted dry ingredients to the meringue. Fold gently with a silicone spatula, scraping around the sides of the bowl and cutting through the center. Add remaining dry ingredients in two more additions, folding until just combined.
Continue folding by spreading the batter against the sides of the bowl to deflate it slightly. Test consistency by lifting the spatula and letting batter fall back - it should form a ribbon that disappears within 10 seconds. The batter should flow smoothly and you should be able to draw a figure eight without the ribbon breaking.
Transfer batter to a piping bag fitted with a round tip. Line baking sheets with parchment paper. Pipe circles about 1.5 inches in diameter, spacing them 2 inches apart. Hold the bag perpendicular to the pan and pipe with steady pressure.
Firmly tap the baking sheets on the counter 5-6 times to release air bubbles. Let piped macarons sit at room temperature for 30-45 minutes until they form a skin that doesn't stick when gently touched.
Preheat oven to 300°F. Bake macarons for 13-15 minutes until they don't wobble when gently touched. Cool completely on the baking sheet before removing.
For the filling: Beat heavy cream until soft peaks form. In a separate bowl, mix mascarpone with powdered sugar until smooth. Gently fold whipped cream into mascarpone mixture.
Match up macaron shells by size. Pipe or spread filling on the flat side of one shell, then sandwich with another shell. Press gently. Refrigerate filled macarons for 24 hours before serving for best texture.