In a large bowl, whisk together flour, baking soda, salt, and cinnamon.
In a separate bowl, add brown sugar, granulated sugar, and butter. Using a handheld mixer, mix until smooth. Add eggs and vanilla extract and beat till well combined. Fold in toffee chips and optional chopped pecans.
I like to reserve a few toffee chips to top the cookie dough. It's totally up to you though.
Refrigerate for 30 minutes.
When you're ready to bake, preheat your oven to 350°F and line a large baking sheet with parchment paper.
Roll 1 tablespoon of cookie dough into a ball and place on your prepared baking sheet leaving 2 inches per cookie for spreading. (If you reserved extra toppings, place them on top of cookie dough now.)
Bake for 12 minutes, or until the edges of cookies are set.
Remove from oven and sprinkle with flaked sea salt, to taste.
Let your cookies cool for 15 minutes on a baking rack. Enjoy!