Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a large mixing bowl, cream together the softened butter, vegetable oil, granulated sugar, and powdered sugar until light and fluffy (about 2-3 minutes).

Add the egg and 1 tsp vanilla extract, mixing until well combined.

In a separate bowl, whisk together flour, salt, and baking powder. Gradually add the dry ingredients to the wet mixture, mixing until just combined.

Using a large cookie scoop, portion out roughly 9 equally sized cookie balls and place them on the prepared baking sheet.

Flatten each cookie to about 1 inch thick, and then create a well in the center to hold the pecan filling.

In a saucepan over medium heat, melt 5 tbsp butter. Stir in brown sugar, chopped pecans, 1 tsp vanilla extract, heavy cream, cinnamon, nutmeg, and a pinch of salt, and cook for 2-3 minutes until warmed through.

Spoon a generous amount of the pecan filling into the well of each cookie.

Bake in the preheated oven for 8-9 minutes or until the edges are golden brown.

Cool the cookies on the baking sheet for a few minutes before transferring to a wire rack to cool completely.