For the base of the tart and the finish
Blend the cookies, the sugar and the butter in the blender, for about 5 minutes.
The consistency of the crumbled mixture needs to be such so as to allow you to form small firm balls in your hands.
Spread the mixture on a baking dish or tart pan, pressing it with your hand across the surface so that the entire surface is evenly covered with the mixture.
Coat the base with the dulce de leche, spreading it evenly.
Refrigerate until the dulce de leche sets.
Top with the chocolate ganache, sprinkle with salt and refrigerate until firm.
Cut into slices, pour caramel sauce on top and serve.
For the dulce de leche
Immerse the closed sweetened milk can in a pot with water and simmer over low heat for about 5 hours.
Let it cool slightly before opening.
Pour the caramelized milk into a mixing bowl and if needed heat it to 40 degrees C.
Add in the cognac and stir until uniform.
For the chocolate ganache
Melt the chocolate in a water bath and keep it warm.
In a pot, pour the cream and heat it until it is about to begin boiling.
Carefully combine the cream and the couverture by pouring in the cream in three increments and continuously stirring until uniform and smooth before pouring in the next increment.