Place the chocolate into a heatproof bowl.

Pour the cream into the bowl with chocolate. Stir until the chocolate has melted and the mixture has a homogeneous consistency. Allow to cool down until warm to the touch.

Add the butter and stir to incorporate. Additionally, you can blend the mixture with an immersion blender to ensure that there are no pieces of chocolate and butter left.

Cover with plastic wrap so it touches the ganache surface and refrigerate for a minimum of 6 hours or overnight.

Sift the almond flour and powdered sugar into a mixing bowl and whisk well to combine.

Place the egg whites and granulated sugar in a mixing bowl and place the bowl over a saucepan with slightly simmering water (double boiler). Ensure that the bottom of the bowl doesn’t touch the water. Heat the mixture, stirring continuously, until the sugar has dissolved. To check, rub a little bit of the mixture between two fingers. If you don’t feel sugar crystals, it’s ready to be whipped.

Using a rubber spatula, gently fold the almond flour mixture into the meringue until the batter slowly falls down from the spatula in a continuous ribbon. You should be able to draw a figure 8 without breaking the batter a couple of times.

Add the coffee powder and fold once or twice to avoid overmixing the batter.

Transfer the batter into a piping bag fitted with a round piping nozzle.

Keep the piping nozzle facing straight down toward the piping surface (0.5” or 1 cm away from it and don’t lift it up during piping) and pipe 34 even 2" or 4cm rounds. Apply even pressure, letting the rounds expand a little bit up and sideways. Stop squeezing the bag and lift it up with a quick twisting motion so the tail will form a small curl on top of the macaron.

Tap each tray a couple of times against the counter to force large air bubbles out. Use a toothpick to burst the bubbles. Then, leave the trays to dry at room temperature. The drying time will vary depending on the humidity levels in your kitchen. On average, it will take 30-40 minutes or until the tops of the macarons are dry to a gentle touch.

Preheat the oven to 275F/135C (with fan), or 305F/150C (no fan).

Bake one baking sheet at a time in the middle of the oven for 15-20 minutes or until the macarons have formed feet and do not jiggle when touched. If your oven has hot spots and you see that macarons rise unevenly, you may rotate the tray after 8 minutes of baking.

Remove from the oven and bake the second batch.

Allow the macarons to cool down completely before assembling.

Take the ganache out of the fridge and stir until slightly softened.

Transfer the ganache into a piping bag fitted with a round piping nozzle.

Pipe approximately 2 tablespoons of ganache on top of each bottom shell.

Cover with the top shell and press gently to attach.

Refrigerate in an airtight container for 4 hours or overnight before serving.