Preheat the oven to 350ºF.
Melt the chocolate in the microwave by heating in 30-second intervals and stirring until the chocolate is fully melted and smooth. Set aside.
Grind the almonds finely in a food processor and stir into the melted chocolate. Stir until fully incorporated. Spread the chocolate almond mixture evenly on the bottom of a tart or pie pan. Set aside.
Combine the egg yolks, sugar, instant espresso, and cocoa. The mixture will be dry and crumbly. Set aside.
Beat all 3 egg whites until you reach soft peaks. Stir a quarter of the whipped egg whites into the crumbly chocolate mixture. The mixture will absorb the egg white and become moist. Continue by folding in the remaining egg whites.
Pour the batter over the chocolate almond crust and smooth it out evenly.
Bake the tart for 25 minutes. Remove from the oven and allow to cool to room temperature before refrigerating the tart for a couple of hours or until completely chilled (this will help firm up the tart). Serve and enjoy!