Preheat the oven to 325 degrees F (165 degrees C).

Combine pecans, brown sugar, and flour in a small bowl. Cut in butter using a pastry blender or 2 knives until pea-size crumbs form. Press mixture into the bottom and sides of a 9-inch tart pan with a removable bottom.

Bake crust in the preheated oven until golden brown, 8 to 10 minutes. Let cool completely on a wire rack, about 30 minutes.

While crust cools, place chocolate in a glass bowl. Set aside. Pour heavy cream into a small saucepan over medium heat; cook until edges of cream just begin to bubble, but do not boil. Pour hot cream over chocolate and whisk until chocolate is melted and incorporated into cream. Let filling cool for 20 minutes.

Pour filling into cooled crust. Chill torte in the refrigerator for 2 hours. Remove sides of pan prior to cutting.