01 - Preheat oven to 350°F.
02 - Combine flour, cocoa powder, granulated sugar, and salt in a mixing bowl.
03 - Cut in cold butter with a pastry cutter or food processor until the mixture resembles coarse crumbs.
04 - Add egg yolk and 2 tablespoons cold water; mix just until dough comes together, adding a bit more water if necessary.
05 - Shape the dough into a disk, wrap in plastic wrap, and chill for 30 minutes.
06 - Roll dough on a lightly floured surface to fit a 9-inch tart pan. Press into the pan, trim excess, and prick the base with a fork.
07 - Line the crust with parchment paper and fill with baking weights or dried beans. Bake for 15 minutes. Remove weights and parchment, then bake an additional 10–12 minutes until the crust is firm. Cool completely.
08 - Heat heavy cream in a saucepan until just below boiling. Pour over chopped dark chocolate in a separate bowl, let stand for 1 minute. Add butter, then stir until glossy and smooth.
09 - Pour ganache into the cooled tart shell. Smooth the surface and chill in the refrigerator for at least 1 hour, until set.
10 - Arrange the halved strawberries over the ganache.
11 - Warm apricot jam and use a pastry brush to lightly glaze the strawberries for a glossy finish, if desired.
12 - Slice the tart and serve chilled or at room temperature.