Preheat your oven to 350°. Line a 13x9 baking dish with parchment paper and set aside.
In a medium bowl, combine flour, salt, and baking soda. Set aside.
In a large bowl, cream the butter and both sugars together until light and fluffy, about 2-3 minutes. Add in the eggs 1 at a time. Then mix in the vanilla extract.
Slowly add the dry ingredients into the wet, mixing until just combined and no flour streaks are visible. Add in both the chocolate chips and toffee bits, mixing until just combined.
Press batter into the parchment paper-lined baking dish and spread evenly (this will be tough because the batter is a bit sticky- it doesn't have to be perfect). Sprinkle extra chocolate chips on top (optional).
Bake for about 25-30 minutes, until the edges are golden brown. If you want soft/chewy cookies, don't overbake! If you prefer them to be a bit more dense/crunchy, keep them in the oven a bit longer.
Let the bars cool before taking them out of the pan, at least an hour. Cut into bars and serve!
Notes
Line your pan with parchment paper for easy removal after baking.
Cover and store at room temperature for up to 5 days. They can be frozen in a freezer-safe container for up to 3 months. To defrost, allow them to sit at room temperature.