Add powdered sugar, whole almonds, and cocoa powder to a food processor. Process until you have a fine powder.

Sift mixture into a large bowl. Set aside.

In the bowl of an electric mixer fitted with the whisk attachment, whisk egg whites on medium-high speed until they are frothy.

Slowly add the granulated sugar, while beating, until the mixture holds stiff peaks.

Add one half of the meringue to the flour mixture and fold it in gently. A

dd the remaining meringue and do the same. The batter should look like flowing lava, thick but able to spread.

Put the batter into a giant ziploc bag and snip off one of the bottom corners.

On a baking sheet covered with parchment paper, pipe out circles approximately 1.5 inches in diameter.

When you are done piping hit the baking sheet against the counter to let any air bubbles settle (This is a very important step).

Preheat the oven to 350 degrees Fahrenheit and let the piped macarons sit out at room temperature for at least 30 minutes. They will develop a film on the top of them and feel a bit dry. If they don't feel like this then let them sit a little longer.

Bake in the oven for 12-14 minutes. Rotate the pans in the oven halfway through to ensure even baking.

When the macarons are done put them on a wire rack to finish cooling.

When they are cool pipe out a small circle of nutella on a macaron and with another macaron (preferably of the same size) press down gently so you make a sandwich and the nutella just reaches the sides of the cookie.