Blend almond flour, powdered sugar, and cocoa powder in a food processor for 15-20 seconds. Sift into a bowl.

Whip egg whites on medium speed until soft peaks form, then gradually add granulated sugar and whip to stiff peaks.

Gently fold the sifted dry ingredients into the meringue until the mixture flows like a thick ribbon.

Pipe even circles of batter onto a parchment-lined baking sheet. Leave ample space between each macaron.

Allow to rest at room temperature for 15-30 minutes until dry, forming a smooth skin.

Preheat oven to 140°C (285°F) and bake macarons for 14-16 minutes until shells puff with smooth tops.

Chop milk chocolate and stir with heated heavy cream until smooth. Mix in remaining cold cream and chill for 4 hours.

Once ganache is chilled, pipe onto a macaron shell, add Nutella, and top with another shell. Chill for at least 1 hour before serving.