1. Preheat the oven to 350 degrees F. Grease a 9 inch pie plate with cooking spray. Set aside.
2. In a small bowl, combine the flour, baking powder, and salt. Whisk until blended. Set aside.
3. In the bowl of a standard mixer, add the butter and brown sugar. Beat with the paddle attachment until smooth. Add the egg and vanilla extract, beat until blended.
4. On low, slowly add the flour mixture. Mix just until the flour is incorporated. Add the chocolate chips and toffee. Mix until just combined.
5. Scrape the dough into the prepared pie plate. Spread evenly with a rubber spatula. Sprinkle additional toffee over the dough.
6. Bake for 27-30 minutes, or until a toothpick inserted into the center comes out clean. Remove from oven and let cool.
7. Cut cookies into wedges and serve warm or at room temperature.
*Note-feel free to try other mix ins-butterscotch chips, white chocolate chips, M&M's etc. These pie plate cookies are also great with ice cream.