This rich and decadent chocolate dessert can be made in cast iron skillets or in smaller tart pans. The cast iron skillet option results in a slightly crisper crust, and a little bit more flavor especially if you're skillet is well-seasoned. Makes one 8-inch tart.
Preheat the oven to 350 degrees Fahrenheit, and have a 8-inch seasoned cast iron skillet handy.
Mix together the flour, powdered sugar, pecans, cornmeal, salt, and cinnamon in a large bowl until blended. Cut the butter into pea-sized pieces over the bowl, stir to coat the pieces in the flour mixture. Use a dough scraper or pastry cutter to chop at the mixture in the bowl to cut the butter into even smaller pieces.
Empty the mixture into the bowl of a stand mixer fitted with the paddle attachment. Add the egg and vanilla extract and mix at medium-low speed until it is just incorporated, taking care not to overwork the dough.
Roll out the dough on a lightly floured piece of parchment paper until it is ¼ inch thick. Flip the sheet over onto the cast iron skillet and peel the parchment sheet off, leaving the dough on the skillet.
Press the dough into the skillet and trim excess dough to form the crust to the pan. Poke the crust in several places with a fork to keep bubbles from forming.
Grease a sheet of aluminum foil and press the greased side snugly onto the crust. Place the skillet in the oven and bake the crust for 15 minutes, then remove and allow to cool for 5 minutes before removing the aluminum foil sheet from the crust. Poke any bubbles that may have started to form with a fork. Set aside.
Whisk together the egg, vanilla extract, and salt in a small bowl and then set aside. Bring the cream to a boil over medium heat, stirring constantly. Pour the cream over the chocolate in a large bowl and stir until the chocolate has melted and the mixture is smooth. Stir in the egg mixture until completely incorporated. Stir in the pecans.