1 cup chopped pecans, toasted (reserve a few to sprinkle on top)
1 tablespoon vanilla extract
2 cups (250g) confectioners' sugar, sifted twice
Place two sheets of parchment paper, crisscrossed, in an 8x8 inch baking dish.
Toast the pecans (if you have not already toasted them) for 7 minutes at 350°F on a parchment-lined baking dish.
Meanwhile, in a large saucepan over medium heat, combine the butter, heavy cream, granulated sugar, brown sugar, and salt to a boil. Stir frequently. Fudge should heat to around 236° to 239°F and not go over 244°F.
Once the fudge reaches 236°F-239°F, remove from heat.
Add the pecans and the vanilla to the hot fudge in the pan. Stir to just combine.
Stir in the sifted confectioners' sugar until it is well combined.
Pour the mixture back into the baking dish, and add a few more pecans on top.
Cool for at least 60 minutes before cutting and serving. Store in an airtight container.