Preheat your oven to 350°F (175°C). Grease a tart pan.

In a bowl, mix almond flour, cocoa powder, powdered sugar, melted butter, and salt until well combined.

Press the mixture into the bottom and up the sides of the tart pan.

Bake the crust for 10-12 minutes, then let it cool.

In a saucepan, heat the heavy cream until it is just simmering.

Remove from heat, add the chopped dark chocolate, and let it sit for 5 minutes.

Stir until smooth.

In a separate bowl, whisk the eggs and vanilla extract together.

Slowly add the chocolate mixture to the eggs, whisking continuously.

Pour the chocolate filling into the cooled tart crust.

Bake for 20-25 minutes, until the filling is set but still jiggles slightly in the center.

Let it cool completely, then top with chopped pistachios.

Refrigerate for at least 2 hours before serving.