In a medium bowl, using an electric mixer, beat the butter and cream cheese until smooth and creamy.Scrape down the dies of the bowl and then add the all-purpose flour. Mix on low speed until until combined.Scrape down the sides of the bowl again and then cover the bowl with a lid or plastic wrap. Refrigerate the crust for 1 hour. 1/2 cup (1 stick) butter, 3 ounces cream cheese, 1 cup all-purpose flour
Preheat the oven to 350℉. Prepare a mini muffin tin and spray with cooking spray; making sure to spray the sides of each mini cup.
Remove the cream cheese dough from the fridge and use a 1 tablespoon cookie scoop to form 24 (1-inch) dough balls. Place each dough ball into a mini muffin cup and press evenly into the bottom and up the sides of the muffin cups.
In a large bowl, using a hand mixer, add the egg, light brown sugar, butter, vanilla extract, and kosher salt and beat until combined.
1 large egg, 3/4 cup packed light brown sugar, 1 tablespoon butter, 1 teaspoon vanilla extract, ¼ teaspoon kosher salt
Reserve 2 tablespoons of the finely chopped pecans (set them to the side in a small bowl) and stir in the remaining chopped pecans until combined.
2/3 cup finely chopped pecans
Fill each muffin cup with 1 teaspoon of the pecan pie filling. Next, sprinkle the reserved chopped pecans evenly over the pecan tassies.
Bake for 15-20 minutes or until golden brown. Remove from the oven and allow them to cool inside the warm muffin pan for 10 minutes.
Remove the pecan tassies from the muffin pan to a serving platter, plate, or cooling rack. Serve warm or let them cool to room temperature and eat them at room temperature.