This recipe from ChocoParis makes the tastiest macaron i've had. Really really chocolatey :)
I had two problems with the recipe.
One was my macs still come out looking grainy, and i think that's caused by me using almond meal as opposed to almond flour - it's not as finely ground and my food processor's not capable of grinding it further.
The second problem was with the recipe itself - like several of the commenters on the page, i found the mix too thick, and it never achieved macaronage. I ended up beating an extra egg white which helped a lot, so i've added that amount into the recipe below.
115 g egg whites (about 4 large eggs), at room temperature
125 g ground almonds or almond flour
125 g icing sugar
25 g unsweetened cocoa powder (optional)
125 g caster sugar divided into two equal portions
125 g dark chocolate
100 ml thickened cream
25 grams unsalted butter
Pulse the almond powder, icing sugar and cocoa powder in a food processor just until a fine powder is obtained. Then sift the mixture into a large bowl. If using almond flour, you may simply sift the almond flour and icing sugar together.
Place the egg whites in a large bowl and add half of the caster sugar. Begin beating the whites and sugar at low-medium speed. After 2 minutes, when the mixture starts to rise and holds its shape, increase the mixer speed. Continue beating at medium speed until firm peaks are obtained. Add the rest of the caster sugar and beat until all the sugar is dissolved.
Add all of the tant pour tant (almond sugar mixture). Using a spatula, gently fold the mixture until the dry ingredients are completely incorporated, taking care not to overmix. The batter should be smooth and glossy and have a lava-like consistency. It should form a ribbon when dripped from the spatula.
Line two baking trays with parchment paper. Fill a large pastry bag half full with batter and, using a plain round tip, vertically pipe the mixture into 3cm rounds. The batter should be fluid enough that the macarons slowly flatten themselves out. Tap the trays against a hard surface a couple of times to remove any air bubbles.
Allow the macarons to sit for 20 to 30 minutes until a “skin” forms and they are no longer wet when lightly touched. I sprinkled cacao nibs on half of them to form the top shells.
Bake at 160 degrees C (325 degrees F) for 12 to 14 minutes. Shells should be smooth and shiny, with the characteristic “foot” or ridge underneath. You can tell when they’re done by very lightly tapping the side with a knife or fork. The macaron top should not slide but remain firmly on its foot.
Remove macarons from the oven. Cool for a few moments and remove with a lifter. They should come off easily.
For the filling
Place finely chopped chocolate in a heat-resistant bowl.
Bring the cream to a boil in a saucepan. Remove from heat and pour over the chocolate. Stir until melted and smooth. Add the butter and stir well. Allow to cool until thickened.
Using a balloon whisk attachment if you have one, beat the ganache until light and fluffy. Spoon into a piping bag with a plain round tip and pipe ganache onto half of the macaron shells. Cover with a matching sized shell and press together gently until filling is evenly spread.
Refrigerate macarons overnight before serving. Allow them to sit at room temperature for an hour or two before serving. They can be stored in an airtight container in the refrigerator for up to a week.