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["For the shells:", "In a medium bowl, whisk together flour, baking soda and salt and set aside.", "In the bowl of an electric stand mixer using the paddle attachment (or by hand), mix together butter, both sugars, egg and vanilla extract until just combined. Slowly add dry ingredients into the wet, mixing until just combined (do not over-mix). Add the mini chocolate chips and fold in by hand.", "Wrap dough tightly in plastic wrap (in the shape of a brick) and chill it for 2 hours, up to a few days.", "Once dough is chilled, it's time to form the tart shells.", "Preheat oven to 350 F and spray a 12-well tart or muffin pan with nonstick spray.", "Remove dough from plastic wrap and place it on a large cutting board. Cut the dough into 12 even pieces (this optional, but it helps make the tarts all the same size).", "Take one of the 12 pieces and line the bottom of a well in the pan. Using your fingers, spread the dough out evenly so it covers the sides and bottom of the well, leaving a hollow pocket in the middle (like a bowl). Use this method to make the other 11 tart shells. Use a fork to prick the bottom of each tart shell dough (to release air so they don't puff up too much).", "Bake them for about 12 minutes (or until the edges just start to turn golden brown). Once they're done, remove pan from oven, set it on a wire rack and allow them to cool for just a few minutes. While they're still warm, gently press back down in the middles a bit to re-form the bowl shape (I used the edge of a mini square cookie cutter).", "Completely cool the shells in the pan on the wire rack until room temperature before removing them from the pan. They must be at room temperature before filling them.", "For the filling:", "Line up the tarts, side by side, on a flat surface, like a cutting board or cookie sheet. Place the chocolate pieces in a heat-proof bowl (preferably with a pouring spout) and set it aside.", "In a small to medium-sized saucepan, bring cream to a boil over medium heat, constantly stirring. Pour warmed cream over chocolate and let it stand for 2 minutes. Then whisk butter into the chocolate mixture, mixing everything until smooth. Let chocolate mixture cool for about 10-12 minutes (stirring every minute or two).", "Fill each tart (once tarts are room temperature) with chocolate mixture. Let tarts stand at room temperature for another 2 hours or refrigerate for at least once hour to set.", "Notes:", "The shells ended up being about 1/2"" thick sides and bottom.", "Depending on the size of your tarts, you might have some extra ganache (which to me, isn't a problem)."]
