Preheat your oven to 350°F (175°C) and line your baking sheets with parchment paper to avoid sticking. This helps your cookies come off easily after baking.

In a spacious bowl, whisk the flour, cornstarch, baking soda, and salt until well combined. This blend will create a great texture for your cookies.

In another bowl, beat the softened butter with both brown and granulated sugars until the mixture is light and fluffy. Add in the egg, egg yolk, and vanilla extract, mixing until fully combined.

Gradually add the dry ingredients to the wet mixture, stirring until the dough just comes together. Don’t overmix to keep the dough soft and tender.

For the pecan topping, melt butter in a saucepan over medium heat. Stir in brown sugar, maple syrup, chopped pecans, and a pinch of salt, letting it cook for a few minutes until it thickens slightly. 

Then stir in heavy cream and vanilla extract, cooking for an additional minute before removing from heat.

Scoop out dough using a spoon or cookie scoop and roll each portion into a ball, about the size of a golf ball. Place them on the baking sheets with space between each ball. 

Refrigerate for at least 5 hours or freeze for 1 hour to prevent the cookies from spreading too much while baking.

Once chilled, bake for 12-13 minutes, or until the edges turn golden brown and the centers are still slightly soft.

When you take the cookies out of the oven, gently press the back of a spoon into the center of each one to create a little well for the pecan topping.

Top each cookie with a generous spoonful of the pecan mixture, then let the cookies cool for a few minutes on the baking sheet. 

Transfer to a wire rack to cool completely.