Cream the ¾ cup butter and 1 cup brown sugar in a large bowl with a hand mixer. Add 1 egg and 1 teaspoon vanilla and mix to combine.
In a smaller bowl, combine the 2 cups flour, 1 teaspoon baking powder, and ½ teaspoon salt; whisk them together.
Add half of the flour mixture to the butter mixture and mix on low speed until flour is incorporated. Add the remaining flour and mix until just combined.
With your clean hands, shape the dough into 1¼" balls and place 2" apart on a cookie sheet.
Spray the back of a rounded teaspoon with vegetable spray (to prevent the spoon from sticking in the dough) and make an indentation in the pecan pie cookie dough.
Transfer the formed pecan cookies to the refrigerator, and chill the dough for 20 minutes or until firm. (This will help the cookies hold their shape).
Preheat the oven to 350°—line two baking sheets with parchment paper and set aside.
In a medium bowl, add the 1 cup chopped pecans, ½ cup brown sugar, ¼ cup heavy cream, 1 teaspoon vanilla for the filling. Stir to combine and set aside.
Add one teaspoon of the pecan filling to the indentation. Sprinkle cookies with a pinch of sea salt. Bake for 8-12 minutes.
Allow the cookies to cool on the baking sheet for 2-3 minutes, then transfer them to a cooling rack.
Mix the 1 cup powdered sugar2 tablespoons bourbon, and 1 tablespoon heavy cream in a small bowl and stir until smooth and creamy.
Drizzle the glaze over the cooled cookies. Let the cookies sit until the glaze dries, and store them in an airtight container, separated by parchment paper.