01 - Preheat oven to 350°F.
02 - In a mixing bowl, combine all-purpose flour, cocoa powder, granulated sugar, and a pinch of salt.
03 - Cut cold, cubed unsalted butter into the dry mixture using a pastry cutter or food processor until it resembles coarse crumbs.
04 - Add egg yolk and 2 tablespoons of cold water. Mix until dough just comes together, adding an additional tablespoon of water if necessary.
05 - Shape dough into a disk, wrap tightly in plastic, and refrigerate for 30 minutes.
06 - On a lightly floured surface, roll out dough to fit a 9-inch tart pan. Press into pan, trim excess, and prick base with a fork.
07 - Line crust with parchment paper and fill with baking weights or dried beans. Bake for 15 minutes, remove weights and parchment, then bake for 10 to 12 minutes more until set and firm. Allow to cool completely.
08 - Heat heavy cream in a saucepan over medium heat until just below boiling. Pour over chopped dark chocolate in a bowl, let stand 1 minute, add butter, then stir until smooth and glossy.
09 - Pour ganache into cooled tart shell. Evenly smooth the surface and refrigerate for at least 1 hour until set.
10 - Neatly arrange halved strawberries over the set ganache.
11 - Warm apricot jam and gently brush over strawberries for an optional glossy finish.
12 - Slice tart and serve chilled or at room temperature.