In a pan over medium heat, combine pecans, heavy cream, brown sugar, butter, vanilla extract, and salt.

Bring to a boil, then reduce heat and simmer for 3 to 5 minutes.

Transfer the mixture to a bowl and let it cool to room temperature.

Whisk together melted butter, granulated sugar, and light brown sugar until smooth.

Add cocoa powder, salt, espresso powder, vanilla extract, vegetable oil, and heavy cream. Microwave for 30 seconds until warm, not hot.

Whisk until smooth, then add eggs and whisk well.

Mix in all-purpose flour until a thick batter forms.

In a small bowl, combine melted butter, sugar, flour, vanilla extract, and salt. Mix until dough forms.

Preheat oven to 350°F (175°C).

Line a 9x9 inch baking pan with parchment paper and press the dough evenly into the bottom.

Pour the brownie batter on top and bake for 25 to 30 minutes until fudgy in the center.

Let it cool to room temperature, then spread the pecan pie layer on top.

Chill in the fridge for 30 minutes until set, then cut into squares and enjoy!