Start by creaming the melted butter, granulated sugar, and brown sugar in a large bowl until it's light and fluffy.

Next, add in the eggs and vanilla extract, mixing until everything is smooth and well combined.

Now, gently stir in the flour, baking soda, cornstarch, baking powder, and cinnamon until just mixed. You want to be careful not to overmix!

Fold in the chopped pecans and toffee bits if you’re using them. Make sure they're evenly spread throughout the dough.

Chill your dough in the refrigerator for about 30 to 45 minutes. This makes it easier to scoop and shape.

Once chilled, scoop out small portions of dough and roll them into balls. The dough may feel a bit crumbly, but warming it in your hands will help it come together.

If you like a little extra sweetness, roll each ball in some granulated sugar before placing them on a parchment-lined baking tray.

Preheat your oven to 350 degrees F and bake the cookies for about 11 to 14 minutes. They should be golden brown around the edges and a bit poofy in the center. They’ll deflate as they cool, but if you want, you can gently press them down with a spoon.