I made this for dessert a few weeks ago, and I absolutely loved it. I added some fudge sauce, and used different cookies in the base, and it turned out great. This was when my oven wasn't working, so I had to try some oven-free recipes for a change.
Here is the recipe. Australia doesn't have graham crackers, or anything close, really. So, I took it as an opportunity to add more chocolate, and I used Arnott's Choc Ripple Biscuits. I added 2 tbsp of white sugar, and omitted the brown.
For the chocolate sauce, I used this recipe from Company's Coming Sweet Cravings, but I slightly changed a few things.
Chocolate Fudge Sauce:
1 cup semi-sweet chocolate chips, or dark chocolate
1/4 cup butter
2/3 cup corn syrup, or glucose derived from corn (which is a lot thicker than corn syrup, but still works fine)
1/2 cup hot water
1 1/2 tsp instant coffee (optional)
1/16 tsp salt
1 cup icing sugar
1 1/2 tsp vanilla
Measure first 6 ingredients into a saucepan and heat over medium until mixture is smooth, and chocolate is melted. Be sure not to burn mixture, and stir constantly. Remove from heat. Sift icing sugar into a bowl. Poor a small amount of chocolate mixture into the icing sugar to form a paste. Poor the rest of the chocolate mixture in, and mix until smooth. Add vanilla and beat. Sauce thickens in the fridge, or add more icing sugar to achieve desired consistency. I find you can really taste the coffee, so it's more of a subtle mocha sauce, I think.