FOR THE CRUST
1 1/4 cups all-purpose flour
2 1/2 tbsp Dutch-processed cocoa powder
1/2 cup sugar
1/4 tsp salt
1 stick cold unsalted butter cut up into 6 pieces
1-2 tbsp ice water
FOR THE CARAMEL
1 cup sugar
6 tbsp unsalted butter, room temperature cut up into 6 pieces
1/2 cup heavy cream
1 tsp salt
FOR THE GANACHE
1/2 cup heavy cream
4 oz extra-bittersweet chocolate finely chopped
Sea salt crystals or kosher salt for garnish
In a large bowl mix flour with cocoa powder, sugar and salt. Incorporate butter to the flour mixture, using a pastry blender, a fork or a pastry processor, until crumbs are formed. Mix in the egg. Add the ice water a tablespoon at a time and mix swiftly and gently.
Flatten the dough into disk, wrap tightly in plastic wrap and refrigerate at least 2 hour or overnight.
Roll the dough out on a floured surface with a floured rolling pin to about 1/4 inches thick. Using a round cookie or biscuit cutter (approximately 3.5 inches diamater) cut rounds out.
Gently press each circle into the wells of a standard cupcake tin. Re-roll and cut scraps as needed until you’ve filled 9 wells in the cupcake tin. Refrigerate for 30 minutes before baking.
Preheat the oven to 350F. Prick the dough with a fork, line a parchment paper over the each cupcake well. Fill with dry beans, rice or pie weights. Bake for 10 minutes, remove the weights and the parchment paper, and return to oven for another 5 to 10 minutes. Allow to cool before removing from the cupcake pan.
Heat sugar in a medium saucepan over medium heat, stirring constantly. Sugar will form clumps and melt into a thick brown, amber liquid as you continue to stir.Be careful not to burn.
Once sugar is completely melted, immediately add the butter. Stir the butter into the caramel until it is completely melted, about 2 minutes. Very slowly drizzle in 1/2 cup of heavy cream while stirring. Allow the mixture to boil for 1 minute. It will rise in the pan as it boils. Remove from heat and stir in 1 teaspoon of salt.
Let the caramel cool slightly and pour into cooled tart shells(about 3 tablespoons) and refrigerate until firm, around 4 hours.
Heat the cream in a small saucepan. When the cream just begins to boil at the edges, remove from heat and pour over the chopped chocolate. Let sit one minute, then stir until smooth.
Pour the chocolate ganache over the caramel. Spread it evenly and refrigerate for another 2-3 hours before serving. Sprinkle with sea salt flakes and serve.