Preheat oven 350F, middle rack. In a stand mixer with paddle, put the butter, both sugars, baking soda, salt and vanilla. Beat on medium just until ingredients come together, adding the baking soda and salt.

Add eggs, one at a time; scrape sides as needed. On low speed, add the flour and beat until incorporated. Add the toffee and chocolate chips and beat until well mixed.

On baking sheets lined with parchment, drop batter by heaping tablespoon, 12 per sheet, max. Bake 11-13 minutes, turning midway until just golden brown on edges. Let cool on racks.