Preheat oven to 375°F. Whisk or sift together flour, baking soda, and salt in a medium bowl.
In a large bowl, use an electric hand mixer or the paddle attachment on a stand mixer to cream together the butter, brown sugar, and granulated sugar until smooth and completely combined. Add the eggs and vanilla extract; beat until light and fluffy. Gradually add the flour mixture, just until combined.
Fold in the butterscotch chips and pecans.
Use a cookie scoop to drop the dough onto parchment paper or silicone-lined baking sheets. Press extra butterscotch chips and pecans into the top of each dough ball (if desired).
Bake for 8-10 minutes, or just until the edges are lightly browned and the centers are still soft. While they’re still warm, sprinkle a tiny pinch of flaky sea salt on top of each cookie. Let cool on the baking sheets for a few minutes, and then transfer to wire racks.
Notes
Don’t Overmix. Whipping the wet ingredients too much or overmixing can add excessive air to the dough, causing the cookies to collapse and spread in the oven.
Line the Baking Sheets. Spraying the baking sheets with cooking spray or greasing with butter or lard creates a slippery surface that causes cookies to spread. Instead, line the baking sheets with parchment paper or silicone mats for “grip.”
Cool Baking Sheets. Never place cookie dough on warm baking sheets.
For bakery-style cookies, place extra pecans and extra butterscotch chips on top of the dough balls before baking.
Do not overbake the cookies, or they can become crunchy and dry. Instead, pull them out of the oven when the edges start to brown lightly. The centers will still look underbaked, but the cookies will firm up as they cool -- maintaining that soft, chewy texture.