s'mores parfait with chocolate custard - Pass the Cookies

Ingredients

• ½ cup whole wheat flour (you can use all-purpose too, but this provides a more nutty flavor)
• about 2/3 cup graham crumbs from about 3 sheets crushed graham crackers
• ¼ cup brown sugar, lightly packed
• ¼ cup flour
• ¼ teaspoon vanilla
• 4 ½ tablespoons butter, cold and cut into 1/2 inch cubes
• 10 ounces bittersweet chocolate, finely chopped
• 5 egg yolks
• 5 tablespoons sugar
• ¼ teaspoon salt
• 1 ½ cups heavy cream
• ¾ cup half and half
• 1 tablespoon water
• ½ teaspoon instant espresso powder
• 1 tablespoon vanilla