Combine all ingredients in a medium bowl until crumbly. Press firmly into a 9" tart pan (sides first, then bottom).*** Bake for 7-8mins. Cool completely in pan.
Dark Chocolate Ganache Filling:
Place chopped chocolate and butter into a large bowl.
In a small saucepan, bring cream just barely to a simmer. Pour over chopped chocolate and cover bowl immediately with plastic wrap. Let stand 5 mins. Stir with a spatula until combined and smooth. ****
Pour into cooled tart shell and allow to set - overnight at room temperature or 1-2 hours in the fridge.
Sprinkle with sea salt and drizzle with dulce de leche (or any other sauce) if desired. Serve at room temperature.
* I used crushed up sugar cookies from a failed recipe.** Do not use baker's chocolate.*** I used a flat metal measuring cup to help press down.**** If you have unmelted chunks of chocolate in your ganache still, you can heat it up over a simmering double boiler on the stove.