Method
Preparation
Preheat your oven to 350°F (175°C).
Whisk together the flour, cocoa powder, powdered sugar, and salt in a large bowl.
Add the cold, cubed butter into the mixture and mix until it resembles coarse crumbs.
Stir in the egg yolk and hydrate with cold water, one tablespoon at a time, until the dough comes together.
Press the dough evenly into a 9-inch tart pan across the bottom and up the sides. Prick the bottom with a fork.
Bake the tart crust for 15–20 minutes until set and slightly firm.
Heat the heavy cream until it just begins to simmer, then remove from the heat.
Add the chopped dark chocolate to the hot cream and stir until smooth.
Whisk together the eggs, vanilla extract, and salt in a separate bowl, then gradually incorporate the warm chocolate mixture.
Pour the chocolate filling into the pre-baked tart crust.
Bake for another 15–20 minutes until the filling is set but still slightly jiggly in the center.
Let cool to room temperature, then refrigerate for at least 2 hours to set completely.
Arrange the fresh raspberries on top once set, and garnish as desired before serving.
Notes
Ensure your butter is cold for a flaky crust and avoid overworking the dough. For a smooth ganache, let the chocolate sit in the hot cream before stirring.