Preheat the oven to 325 degrees. Line a baking sheet with nonstick aluminum foil.
In the bowl of a stand mixer, cream together butter and sugar using the paddle attachment. Add the vanilla, pecans, toffee pieces and flour to the stand mixer and mix on the lowest speed until well combined. Add the egg and mix thoroughly until the dough comes together.
Using a medium-side cookie scoop, scoop the cookies onto the cookie sheet leaving about 1-inch between them. Don’t worry, they don’t spread much.
Bake for 20-22 minutes until lightly golden around the outsides.
Remove from the oven and immediately begin transferring the cookies one at a time to a bowl with confectioners sugar. (Note: the cookies are fragile at this point, so you want to touch them as gingerly as you can.) Gently coat with confectioners sugar and transfer to a cooling tray. (Hint: set it over a second baking sheet to catch the excess sugar.) Continue until all the cookies have been coated. Sprinkle any additional sugar over the cookies and let cool completely before enjoying.
Recipe by Sarah's Cucina Bella at http://sarahscucinabella.com/2013/12/08/pecan-toffee-wedding-cookies/