Preheat the oven to 350 degrees F.
Place the butter in a small saute pan and place over medium heat. Completely melt the butter, then cook until the butter is brown and smells nutty, an additional 3 to 4 minutes. Take off the heat and allow to cool.
Place the granulated sugar and brown sugar in the bowl of a stand mixer. Pour in the cooled butter and beat on low to medium speed until smooth and fluffy, 3 to 4 minutes. Add the vanilla extract and eggs and continue to beat on low until the mixture is combined.
Combine the flour, baking soda and salt in a separate bowl and slowly incorporate into the batter a little at a time. Beat until smooth. Fold in the butterscotch chips and pecans.
Line 2 baking sheets with parchment. Using a 1-ounce scoop or a tablespoon measure, portion out the cookie dough, leaving 2 inches between each cookie. Sprinkle the cookies with salt and bake until golden brown, 10 to 12 minutes.