Preheat the oven to 365 F and line an 8-inch square baking pan with parchment paper so it sticks out over the edges of the pan on at least two sides (this will help you lift the bars from the pan after baking).

Add all the ingredients for the shortbread base to a bowl and mix until you get a soft dough. 

Place the dough in the prepared pan and press down firmly with your hands until you have an even layer. Poke approximately 15-20 evenly spaced out little holes in the crust using a fork.

Bake the crust for 13-15 minutes, then remove from the oven and set aside. While the crust is baking, begin preparing the pecan filling.

In a small bowl, mix the cornstarch and water into a paste and set aside.

Add all of the filling ingredients except for the pecans to a small pot on the stovetop and cook over low to medium heat until thick, smooth and fully combined.

Add the cornstarch mixture and cook for a few more seconds, stirring until fully incorporated and starting to thicken.

Remove the pan from the heat and stir in the pecans until they're fully coated.

Pour the mixture over the crust and and bake for 20-25 minutes.

Let cool at room temperature until you can safely place in the fridge. Cool in the fridge for at least 1 hour before slicing and serving.