To make giant toffee chocolate chip cookies, first you need to prepare your ingredients. First, you'll need your flour, baking powder, sugar, salt, and cocoa powder. Then, add your wet ingredients to the dry ingredients and mix them together until they're well combined. Next, preheat your oven to 350 degrees F (180 degrees C). Line a cookie sheet with parchment paper and grease it with non-stick cooking spray. In another large bowl, mix together your chocolate chips, butter, brown sugar and vanilla extract. Pour the batter into the prepared baking sheet. Bake the cookies for 12 to 15 minutes or until the edges are golden brown. Remove from the oven and let cool for 5 minutes before transferring to wire racks to cool completely.