Prepare two baking sheets with parchment paper and set aside.
In a medium-sized bowl, whisk together the flours, baking powder, baking soda, and salt. Set aside
In a large bowl, use a stand mixer or hand mixer to cream the butter, about 30-45 seconds. Add in the sugar and continue to cream the butter mixture. Once the mixture is a pale yellow, add in chocolate chips and toffee pieces.
Gradually add in the flour mixture to the butter mixture. The mixture will be a bit crumbly, so don't worry if it looks off. Add in eggs and mix until fully combined.
Make the cookie dough balls. Each ball should weigh around 6 oz or ¾ cups. The dough should make around 5-7 large cookies. Place the large balls of dough on a prepared tray and place in the freezer for 90 minutes.
When the cookies are almost ready, preheat the oven to 375°. In order to get a solid cook, place one empty baking sheet upside-down in the oven and place the tray with the cookie dough on top of it. Bake for about 26 minutes, or until the edges show a golden brown tint.
Let the cookies cool completely and enjoy. The cookies will last about a week in an airtight container.