Preheat oven to 350F and line a cookie sheet with parchment paper.

Spread pecan halves evenly over cookie sheet and bake on 350F for 3-5 minutes.

Remove from oven and coarsely chop (do not turn off your oven). Set aside.

In a large bowl, combine melted, cooled 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 1/2 Tablespoon onto prepared cookie sheet, spacing at least 2" apart.

Transfer to 350F oven and bake for 10-12 minutes. Allow to cool completely on baking sheet before enjoying!

Store any leftover, cooled cookies in an airtight container at room temperature for 3-5 days.