1cup(226g) unsalted butter, cold and diced into small cubes
2/3cup(86g) powdered sugar
1 1/2tspvanilla extract
1/2cup(60g) finely chopped pecans, plus more for garnish**
9ozchopped good quality milk chocolate or dark chocolate, broken into pieces or chopped***
In a mixing bowl whisk together flour and salt, set aside. In the bowl of an electric stand mixer fitted with the paddle attachment cream together butter and powdered sugar, while stopping to scrape down bowl frequently, until mixture is smooth and creamy. Mix in vanilla extract then with mixer set on low speed slowly add in flour mixture and mix until nearly combined (it will be dry and crumbly at first but it will start to come together). Add in toffee bits and pecans and mix until combined (you may need to fold in those at the bottom of the bowl with a spatula). Divide dough into 2 equal portions. Shape each portion into an even 6 1/2-inch log (that is about 1 3/4-inches round) on a lightly floured surface compressing dough rather tightly together so there aren't holes in the center of the log and cookies hold together well when sliced. Wrap each portion in a separate sheet of plastic wrap. Chill dough 1 hour. Preheat oven to 350 degrees during last 15 minutes of chilling dough.
Remove one log of dough from refrigerator. Cut into slices slightly under 1/2-inch thick. Transfer to a baking sheet lined with parchment paper spacing them 2-inches apart. Bake in preheated oven until just barely golden brown on edges, about 12 - 16 minutes. Let cookies cool 5 minutes on baking sheet then transfer to a wire rack to cool completely. Repeat process with remaining chilled dough, adding the sliced dough to a cool baking sheet (a warm baking sheet will make them spread more).
For the chocolate coating:
Line two baking sheets with parchment paper. Add chocolate to a medium microwave safe bowl. Heat in microwave in 20 second intervals on 50% power stirring between intervals until melted and smooth. Dip half of each cookie into chocolate, shake to let excess run off. Transfer to parchment paper. Sprinkle each cookie with a little bit of toffee bits and pecans. Let chocolate set at room temperature or in refrigerator to set quicker. Store in an airtight container at room temperature.
*To measure scoop flour from container and level with a butter knife, rather than spooning into cup and measuring. Be careful not to pack into cup when measuring though. For best results just use a kitchen scale, I always use a scale now when I bake and I highly recommend them.
**I like to use Fishers pecan cookie pieces, they are just tiny pecan pieces - no chopping is required and they are all about the same size.
***Note that since the chocolate isn't tempered it may bloom and become lightly streaky or spotty in places, if you want to avoid this you can temper the chocolate or use good quality chocolate melts.