Preheat your oven to 350°F (175°C) and line your baking sheets with parchment paper.

In a large mixing bowl, combine softened butter, granulated sugar, and brown sugar. Beat with an electric mixer on medium speed until light and fluffy.

Beat in the eggs one at a time, ensuring they are fully incorporated. Add in the vanilla extract and mix until combined.

In a separate bowl, whisk together the all-purpose flour, baking soda, baking powder, and salt.

Gradually add the dry ingredients to the butter mixture, mixing on low speed until just combined. Be careful not to overmix.

Fold in toffee bits and chopped cashews until evenly distributed throughout the dough.

Using a cookie scoop or tablespoon, drop dollops of dough onto the prepared baking sheets, spacing them about 2 inches apart.

Bake in the preheated oven for 12-15 minutes or until edges are lightly golden.

Immediately sprinkle each cookie with a pinch of flaky sea salt after removing them from the oven.

Let the cookies cool on the baking sheets for about 5 minutes before transferring them to wire racks to cool completely.