For the Crust:
Preheat oven to 375 degrees F/190 degrees C. Lightly grease a 9-inch tart pan or 4 small tarts pans.
Place all ingredients for the crust into a food processor, and mix until combined well. Press the mixture into prepared tart pan (or 4 small tart pans), using the back of a small spoon (the mixture will have a crumbly texture). Refrigerate crust for 15 minutes. Bake in preheated oven for 25 to 30 minutes. Let crust cool.
For the Filling:
Break the chocolate into pieces in a large glass bowl placed over a saucepan of boiling water. Stir occasionally until melted. Remove from heat, and stir in the 2 tbsp. butter until melted. Mix in the heavy cream, and whisk until smooth.
Spread the blueberries over the tart crust, then pour the chocolate mixture evenly over the top. Chill in refrigerator for at least 3 hours, so that the chocolate sets. Garnish with walnut halves.
Makes 6 to 8 servings.
Date: September 26, 2006