½cupHeath Toffee bitsoptional, but recommended! (120g)
Preheat oven to 350F (175C) and line a cookie sheet with parchment paper.
Spread pecan halves evenly over cookie sheet and bake on 350F (175C) for 3-5 minutes.
Remove from oven (do not turn off your oven) and set aside while you prepare your cookie dough.
In a large bowl, combine melted butter and sugars. Stir well.
Add eggs, egg yolk, and vanilla extract and stir until well-combined.
In a separate, medium-sized bowl, whisk together flour, cornstarch, baking soda, baking powder, and salt.
Gradually add flour mixture to wet ingredients until completely combined.
Add chopped pecans and toffee bits (if using) and stir well.
Line cookie sheets with parchment paper and drop cookie dough by heaping 1 ½ Tablespoon onto prepared cookie sheet, spacing at least 2" apart.
Transfer to 350F oven and bake for 10-12 minutes. Cookies should still look soft/slightly under-done in the centers. Allow to cool completely on baking sheet and they will finish baking through as they cool but will stay nice and soft!
*If your butter is scorching hot it will melt your sugars and your cookies will spread all over your baking pan. The butter can still be warm, but should not be hot.**If you are using cups, the best way to measure out your flour is to stir it in its bag/container then spoon it into your measuring cup and level off the measuring cup. Packing in your flour (over-measuring it) will leave you with a dry/crumbly cookie dough.Store any leftover, cooled cookies in an airtight container at room temperature for 3-5 days.