Preheat oven to 350 degrees F. Line an 8-by-8-inch square baking pan with parchment paper or foil.

Lightly toast the pecans first, spread on a baking sheet in the oven for 2 to 3 minutes or until fragrant (keep a close eye on them as they can burn quite easily).

To prepare shortbread, combine flour, brown sugar, cornstarch and salt in a mixing bowl or the bowl of a stand mixer.

Sprinkle over cubes of cold butter, then mix until the butter breaks up into lentil-sized pieces (finer than you would want for a pie crust).

Sprinkle over vanilla and mix to combine.

The shortbread will appear very dry and crumbly, but should stick together when squeezed in your hand.

Pour into prepared baking pan. Spread crumbs evenly over the bottom of the pan, then use our hand or a spatula to press the crumbs firmly into the pan, leaving a slightly raised border around the edges.

Bake shortbread for 20 to 25 minutes or until the top appears less shiny and the edges just barely start to turn golden brown.

While shortbread is baking, prepare the filling by combining brown sugar, corn and maple syrups, cream, salt, and vanilla in a saucepan, stirring until sugar is evenly moistened.

Set over medium heat and bring to a frothy boil, stirring regularly.

Remove from heat and stir in toasted chopped pecans, then pour over shortbread layer, spreading nuts out evenly.

Bake for 18 to 22 minutes or until top is covered in small bubbles and no longer jiggles when you wiggle the pan.

Remove from heat and let cool on a wire rack until lukewarm, then refrigerate for at least an hour to fully set the layers.

Cut chilled bars into 16 squares. Serve cold or at room temperature as desired. Bars will keep, refrigerated in an airtight container, for up to 2 weeks, or frozen for up to 2 months.