Cream the butter and sugar with a hand mixer or whisk until smooth and well combined.

Add the egg and vanilla extract and beat just until incorporated.

Sift in the flour, baking powder, and salt. Mix with a rubber spatula, pastry knife, or fork until no dry ingredients remain and the dough has a clumpy texture. Avoid overmixing; the dough should resemble streusel or crumble pie dough.

Press the dough evenly into the bottom of the prepared pan.

Bake for 15 minutes, or until the dough is no longer shiny and begins to turn golden at the edges.

Remove from the oven and let cool for 15 minutes, or until firm. To speed up cooling, place the crust in the fridge or freezer. Keep the oven on while preparing the filling.

Add the sugar, water, and lemon juice to a heavy-bottomed saucepan. Mix until it resembles wet sand, then place it over medium heat. Let the sugar melt and caramelize to a deep amber color.

Meanwhile, pour the heavy cream into a microwave-safe bowl and heat until warm.

Once the sugar syrup has caramelized, pour in the cream in 2–3 batches to prevent excessive bubbling. Whisk vigorously until fully incorporated.

Remove from the heat and add the butter, whisking until completely combined.

Add the salt and whisk, then let the mixture cool in the fridge for 5 minutes.

Add the eggs one at a time, whisking well after each addition.

Stir in the pecans until evenly combined.

Spread the pecan filling evenly over the cooled crust. Bake for 25 minutes.

Remove from the oven and let cool to room temperature in the pan, or place in the freezer to speed up cooling.

Once cooled, cut into 10–12 bars and serve.